2014 Annual Meeting Poster Abstracts
NV Center Diamond:
Kristiaan De Greve and Nathalie de Leon
Quantum Optics in the Solid State with Diamond Nanophotonics
Nathalie P. de Leon, Ruffin E. Evans, Kristiaan De Greve, Alex A. High, Matthew Markham, Alastair Stacey, Daniel Twitchen, Marko Loncar, Hongkun Park, and Mikhail Lukin
Large-scale quantum networks will require efficient interfaces between photons and stationary quantum bits. Nitrogen-vacancy (NV) centers in diamond are a promising candidate for quantum information processing. They act as artificial atoms in the solid state that can be addressed optically, exhibit spin-dependent fluorescence, and can have transform-limited linewidths at the zero phonon line (ZPL). We have coupled NV centers in bulk diamond to photonic crystals and waveguides, with the goal of enhancing emission into the ZPL and realizing the high cooperativity regime for applications such as entanglement of distant NV centers, quantum networks and single photon transistors.
Doping Nano Diamonds
Adrianne Hargrove, Gary L. Harris, James Griffin, Bokani Mtengi
Quantum networks require interfaces between photons and quantum bits. Nitrogen vacancy (NV) centers in diamond are a promising candidate for this interface: they are optically addressable, have spin degrees of freedom with long coherence times, and can be easily integrated into solid-state nanophotonic devices. The crucial optical feature of the NV is its zero-phonon line (ZPL), a cycling transition allowing coherent optical manipulation and read-out of the spin. However, the ZPL only accounts for 3-5 % of the NV emission, and previous methods of producing NV centers yield unstable ZPLs. We will present methods for controlling NV emission by coupling NV centers to nanophotonic devices. In particular, we create a high-density layer of NVs with stable ZPLs in high purity diamond; carve waveguides out of the diamond substrate; and fabricate high quality factor, small mode volume photonic crystal cavities around NVs in these waveguides. We observe an enhancement of the NV emission at the cavity resonance by a factor of 100. These devices will become building blocks for quantum information processing such as single photon transistors, enabling distribution of entanglement over quantum networks.
Modeling Improved Magnetometry through Purcell Enhancement of NV Centers with Bowtie Apertures.
Jeffrey Holzgrafe, I-Chun Huang and Marko Loncar
Nitrogen vacancy (NV) centers have shown great promise for nanometer scale magnetometry, which could allow direct MRI of biomolecules. Higher photon collection rates from these single emitters improves the sensitivity of the measurements. We model the use nanoscale bowtie plasmonic apertures to improve spontaneous emission of NVs in nanodiamonds.
Probing Magnetic Noise Next to a Conductor With a Single Spin Qubit
Shimon Kolkowitz, Arthur Safira, Alex High, Robert Devlin, David Patterson, Quirin P. Unterreithmeier, Alexander S. Zibrov, Vladimir E. Manucharyan, Hongkun Park, and Mikhail D. Lukin.
Noise emanating from conductors and their surfaces can limit the coherence times and relaxation rates of many promising quantum information systems, ranging from superconducting qubits and gate-defined quantum dots to atoms and ions on chips. Here we present experimental results demonstrating the use of single electronic spin qubits in diamond to probe the spectral, spatial, and temperature dependent properties of magnetic noise near conductors. Using nitrogen vacancy (NV) centers implanted at shallow depths we investigate the spectral properties of the magnetic noise at distances down to 10 nm from the metal surface, a length scale not currently achievable in other systems, over a wide range of temperatures, from ~6 to 300 K. We measure a breakdown of OhmÃ¢â‚¬â„¢s law due to the ballistic motion of electrons in the metal, requiring the introduction of a nonlocal dielectric function to account for the observed spin relaxation rates.
Dyanmic Actuation of Single Crystal Diamond Nanomechanical Resonator
Young-Ik Sohn, Michael J. Burek, Marko Loncar
We demonstrate dynamic actuation of single crystal diamond nanobeams in the very high frequency regime for the first time. Applying dielectrophoretic transduction, actuation can be achieved without compromising diamond’s superior optical and mechanical properties.
Constructing a Confocal Microscope to Image Nitrogen Vacancy Centers
Jordan Stroman, Gary L. Harris
CIQM envisions that atomic memory will be achieved using nitrogen vacancy centers (NV). Howard University is optimizing the process of creating nitrogen vacancy centers using hot filament chemical vapor deposition (HFCVD). In order to provide reliable feedback concerning the presence, concentration, and orientation of these color centers, an optical system capable of performing confocal laser scanning fluorescence microscopy is being constructed. This system consists of a 200mw laser that emits light with a wavelength of 532nm. It utilizes a piezoelectric stage with a resolution of 20nm in the x, y and z direction. The detector in this system is an avalanche photodiode with a minimum noise equivalent power of 0.29pW/âˆšHz. When completed this optical system will be able to confirm and locate NV centers with a resolution of ~ 200nm.
Patterned Growth of Photonic Nanostructures from Single-crystal Diamond
Xingyu Zhuang, Evelyn Hu
Negatively-charged nitrogen vacancy centers (NV) in diamond have diverse applications in quantum information processing and sensing. Optical cavities created from single-crystal diamond provide emission enhancement and improve light collection efficiency from NVs. However, most existing techniques for fabricating these structures require top-down processing (e.g. ion implantation, reactive ion etching). These methods can damage the diamond host lattice, which degrades the NV spin and spectral properties, and are challenging for deterministic positioning of NVs. We have designed a nanopillar-based photonic crystal cavity and explored patterned growth to create nanostructures directly from single-crystal diamond. Using chemical vapor deposition with a lithographically-defined mask, we have successfully grown low-aspect ratio diamond nanopillars. Initial characterization shows narrow Raman linewidths and bright luminescence from NVs and silicon vacancy centers in the grown structures.
Diamond, Graphite & Graphene Investigations for High School Physics Students
High School physics lab curriculum seldom introduces students to material science and contemporary research. In an effort to provide such enrichment for Advanced Placement Physics students, four exploratory investigations were developed. Two are explorations of physical properties of diamonds: index of refraction and thermal conductivity. Two are explorations of graphite: graphene synthesis using the tape cleaving method and graphite circuit sketching. The four-lab sequence encourages original experimental design and exposes students to contemporary research practices and modern equipment and materials.
CIQM Lab Modules for Undergraduates
Rebecca Christianson, Abe Levitan
Part of the CIQM's goal is to introduce undergraduate students to quantum materials and get them excited to enter the field. We are developing 2 labs for an undergraduate class about quantum materials that demonstrate the quantum Hall effect and Raman scattering in graphene. These labs demonstrate the fascinating properties of graphene firsthand.
Searching for Nonvolatile Quantum Anomolous Hall Effect in a Hard Ferromagnetic Topological Insulator
Chang, Cui-Zu; Zhao, Wei-Wei ; Chan, Moses H. W. ; Moodera, Jagadeesh S.
Quantum anomalous Hall effect (QAHE), a quantized version of AHE has been theoretically predicted and experimentally observed  in thin films of Cr doped (Bi,Sb)2Te3, a topological insulator (TI). The observation of QAHE in Cr doped TIs usually requires external magnetic field to align magnetic domains before entering into QAH state, and also that these systems have low coercivity (~0.1T). Here we report our findings on a highly promising TI system that enables effective tuning of chemical and electronic properties; the vanadium (V) doped ferromagnetic TI thin films. By molecular beam epitaxial growth and V doping, we have realized both n-type and p-type conductivity in 6nm (BixSb1-x)2Te3 thin films. Remarkably, V doped TI films show strong ferromagnetic behavior with giant coercivity (up to ~1.3T) and high Curie temperatures (up to ~160K). Notable in this case is that the ferromagnetic behavior was found to be independent of the type and concentration of carriers. Moreover, the anomalous Hall effect was observed to be significantly enhanced at low carrier concentration regime, with the anomalous Hall angle reaching an unusually large value of 0.2. It indicates when the carries changes from n- to p-type (lowest carrier density), bulk contribution to conduction reduces and the surface contribution begins to dominate. These findings demonstrate that V doped topological insulators provide a new platform for TI based spintronic development.
Theoretical Studies for Bismuth-Antimony Alloy
Shiang Fang, Bertrand I. Halperin, Efthimios Kaxiras
In history, bismuth has been used to developed experimental condensed matter Fermi-surface tools. Recently, theoretical progress in topological insulator sheds new light on the application with bismuth nanowires and bismuth-antimony alloy. In our work, we construct the simplified tight-binding models from accurate density functional theory calculation to study the real material property.
Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
Xiaofeng Qian, Junwei Liu, Liang Fu and Ju Li
We predict a new class of large-gap quantum spin Hall insulators in two-dimensional transition metal dichalcogenides with 1T’ structure, namely, 1T’-MX2 with M=(Mo, W) and X=(S, Se, and Te) by first-principles calculations. The structural distortion causes an intrinsic band inversion between chalcogenide-p and metal-d bands, and spin-orbit coupling opens a gap at finite momentum, which is highly tunable by vertical electric field. This motivates us to propose a topological field effect transistor made of these atomic-layer van der Waals heterostructures with multiple topologically protected transport channels, which can be rapidly switched off by electric field through topological phase transition instead of carrier depletion.
Exfoliation of Bismuth as a Topological Insulator
Benjamin Panga, Quinton Barclift, Tito E. Huber
At a thickness of 50 nm or below, bismuth is predicted to act as a topological insulator. The research focused on using different methods of exfoliation to obtain thin films of bismuth with thickness of 50 nm or less, where it is transparent. The bismuth particles that resulted from the methods we tried were investigated by using optical imaging devices. No evidence of transparency in our bismuth images suggest that the thickness desired was not achieved.
Preparing Devices to Investigate the Quantum Interface Between Graphene and Topological Insulators
Chinonye Pat-Ekeji, Tina Brower-Thomas
According to Moore's law, in order to keep up with the demands of technology, the number of transistors in electronic devices have to double every two years. The current solution is to make transistors smaller. However, the material used to make transistors is quickly approaching its minimal functional size. The Center for Integrated Quantum Materials endeavors to make a device that incorporates graphene, NV centers in diamond and topological insulators. The purpose of my project is to investigate the interplay of optical and electronic properties between graphene and topological insulator nanowire. High resolution microscopes will be employed to study the current/voltage relationship between single layer graphene and topological insulators. The two devices needed for this research are a graphene test bed, and an atomic force microscope probe tip with a topological insulator (TI) nanowire attached. I have made a graphene test bed employing techniques such as graphene transfer from copper to silicon, lithography. I tested the viability of the graphene using Raman spectroscopy.
Induced Superconductivity in Topological Insulators
Hechen Ren , Sean Hart, Timo Wagner, Philipp Leubner, Mathias Muehlbauer, Christoph Bruene, Hartmut Buhmann,
Laurens Molenkamp, Amir Yacoby
Combining two-dimensional topological insulators with superconductivity can provide us a platform to observe and manipulate localized Majorana fermions. In the context of condensed matter, these are emergent electronic states that obey non-Abelian statistics and can serve as the basis for topological quantum computing. Our experiment has demonstrated promising evidences towards the realization of such states.
Novel Modes and Physics of Fractional Quantum Hall Effect
Oles Shtanko, Leonid Levitov
Fractional Quantum Hall Effect is a window into the world of topological states. Observed firstly at 1982, this phenomenon is still a subject of extensive study. There are few reasons for this. The first is possibility of experimental observations. The second is well defined approaches which let us see deeply into physics of topological states. As example, we consider important 2/3 state. Previous theoretical predictions give us suggestion about existence of unique neutral modes on the edge of FQHE phase. Recent experimental results may support this idea. We discuss physics of observed phenomenon and propose ways to find additional properties of the_system.
Marcha I. Chaudry
The Characterization of Graphene through Raman Spectroscopy
Marcha Chaudry, Charles Hosten
Using Raman spectroscopy to characterize graphene. Explaining the different methods used to grow graphene and why Raman spectroscopy is best used for the characterization.
Capacitance Measurements on Transition Metal Dichalcogenides
Ahmet Demir, Raymond Ashoori
Transition metal dichalcogenides (TMDCs) are layered materials with tunable direct bandgap structure. This feature allows to be open to a variety of applications and rich physics. We aim to understand the physics of these materials using capacitance measurements.
Semiconducting-to-metallic Photoconductivity Crossover in Graphene
A. J. Frenzel, C. H. Lui, Y. C. Shin, J. Kong, and N. Gedik
We investigate the transient photoconductivity of graphene at various gate-tuned carrier densities by optical-pump terahertz-probe spectroscopy. We demonstrate that graphene exhibits semiconducting positive photoconductivity near zero carrier density, which crosses over to metallic negative photo- conductivity at high carrier density. These observations can be accounted for by the interplay between photoinduced changes of both the Drude weight and carrier scattering rate. Our findings provide a complete picture to explain the opposite photoconductivity behavior reported in (undoped) graphene grown epitaxially and (doped) graphene grown by chemical vapor deposition.
Graphene-on-Boron Nitride Sample Fabrication
Andrew Lin, Robert M. Westervelt
During the summer of 2014, work in the Westervelt lab has continued on the development of high-quality graphene-on-boron-nitride (G-BN) samples for capacitance measurements. Graphene deposited via epitaxy on special mounting points is in turn layered on boron nitride deposited on silicon via epitaxy. Through the use of flip-chip bonding followed by lithography/evaporation of leads onto graphene on boron nitride, the lab is attempting to observe high-mobility samples for use in our experiments, an ongoing process which promises viable results for use in sample fabrication.
Physical Adsorption of Molecules on a Monolayer Graphene Sheet
Sidi Maiga, Silvina Gatica
We present results of Grand Canonical Monte Carlo simulations of adsorption of Kr, Ar Xe and CO2 on a monolayer graphene sheet. We compute the adsorbate-adsorbate interaction by a Lennard Jones potential. We adopt a hybrid model for the graphene-adsorbate force; in the hybrid model, the potential interaction with the nearest carbon atoms (within a distance rnn) is computed with an atomistic pair potential Ua; for the atoms at r>rnn, we compute the interaction energy as a continuous integration over a carbon uniform sheet with the density of graphene. For the atomistic potential Ua, we assume the anisotropic LJ potential adapted from the graphite-He interaction proposed by Cole et.al. This interaction includes the anisotropy of the C atoms on graphene, which originates in the anisotropic Ï€-bonds. The adsorption isotherms, energy and structure of the layer are obtained and compared with experimental results.
Growth of Molybdenum Disulfide Films on Silicon Wafers
Christopher Mbochwa, Paul Sabila
Our research is interested in electronic properties of molybdenum disulfide (MoS2) nanomaterials. The overall goal is to develop a process for large-scale synthesis of MoS2 wafers. A silicon semiconductor has transformed the computer and electronic industry but the current computer processors based on silicon technology is reaching its limit. MoS2 paves the way for the development of totally new domain of electronic devices and materials to replace silicon based semiconductors. The band gap of MoS2 allows for their usage in fabricating transistors. MoS2 together with other 2D and thin-film materials are applied in flat light-emitting devices and also in transparent electrodes found in large-screen displays such as television sets and computer monitors.
We have prepared some MoS2 films on silicon and silicon oxide wafers. The first step involved the intercalation of bulk MoS2 by using n-butyl lithium for 48 hours. Exfoliation was achieved by adding the reaction mixture to distilled water. The exfoliated MoS2 films were then analyzed by Scanning Electrons Microscope (SEM) and Energy Dispersive Spectroscopy (EDS). SEM analysis showed the MoS2 films deposited on silicon wafer. EDS confirmed that MoS2 was actually deposited with ratio of Mo:S roughly equals 1:2.
How Sensitive is graphene? Graphene Based Sensors
Tabia Muhammad, Silvina Gatica
The experiment I was to study is based on graphene and its sensitivity. I was to find the missing parameters. Graphene was used as a substrate. It has very unique properties. Graphene is made up of a single layer of carbon. The experiment resulted in graphene being super sensitive despite its environment. Graphene based sensors will be used based on its properties in time to come.
Growth of Graphene on Different Substrates
Mpho Musengua, Gary L. Harris, Crawford Taylor, Tony Gomez
Graphene is a two dimensional, one atom thick allotrope of carbon derived from natural graphite; it has unique properties of being the strongest material ever measured, the thinnest material known to science, the stiffest material in the world, it is transparent, stretchable, highly flexible and incredibly light, it is the most impermeable material on earth, it is the worldâ€™s most conductive material and incredibly energy efficient. These properties make graphene suitable for future applications such hydrogen storage, lighter prosthetics, and flexible electronics. Graphene holds the potential to bring about a new era in material science. The greatest challenge to commercializing graphene is being able to produce high quality material, on a large scale at a low cost and in a consistent reproductive manner. Past methods of graphene preparation such as exfoliation are efficient for lab purposes, but are not suited for mass production. With applications in mind, suitable substrates and methods for large quality graphene growth are necessary. This project focused on how various substrates affect graphene growth and which methods of graphene growth are suitable for different substrates. Graphene was grown by the following methods: simple chemical vapor deposition (CVD) and radio frequency CVD (RFCVD). The methods were selected because they provide the option to use various substrates under unique conditions. From these methods, graphene growth was attempted on the following substrates: copper, 3C-silicon carbide on silicon, nickel, nickel chrome, and nickel films on 3C-silicon carbide. These substrates were selected due to their properties of strength, ductility, and resistance to corrosion and heat. The substrates were characterized using scanning electron microscopy and Raman spectroscopy. Raman results have confirmed graphene on nickel films on 3C-silicon carbide. Raman results to verify graphene on the other substrates are ongoing.
Electric Double Layer Gating of Transition Metal Dichalcogenides
Efren Navarro-Moratalla, Hugh Churchill, Yafang Yang, Pablo Jarillo-Herrero
Charge carrier control is a keystone in the electronic technologies of semiconducting materials. Conventional transistor techniques (ie. gating through a solid-state dielectric barrier) have permitted the modulation of the electrical transport across 2D crystals, giving rise to the observation of a variety of new physical phenomena. However, this type of electrical field has been found to allow for maximum carrier densities of around 1013 cm-2. The use of ionic liquids as gating electrodes gives rise to the formation of high capacitance electrical double layers (EDLs) that permit exploring much higher carrier density regimes (up to ca. 10^15 cm-2), opening the door for the study of field-induced correlated states, such as ferromagnetism or superconductivity.
Though reported experiments have failed to show direct evidence of superconducting behaviour in exfoliated graphene, pioneering works on transition metal dichalcogenides have provided with direct proof of the use of EDLs for the induction of superconductivity in the surface of bulk crystals (for instance ZnS2), or in the surface of thick flakes (such as in MoS2 or in ZrNCl). And yet, no reports of single layer superconducitivty have been put forward.
Herein we take advantage of the EDL approach, the wide range of tuneable-band-gap semiconducting transition metal dichalcogenide and the van der Waals heterostructure technique to fabricate high quality ultraflat samples that will permit exploring the high carrier density regime in search for switchable single layer superconductivity. The use of a liquid gate also opens the possibility of studying the effect of strain or even the presence of molecular species (sensing) may have in the superconducting state.
Selective N-Type and P-Type Doping of Graphene with Functionalized Gold Nanoparticles and Electron Acceptor Molecules
Raymond Otchere-Adjei, Charles M. Hosten
Spatially selective doping of graphene with photoreactive groups, such as electron-rich metal nanoparticles, has potential applications in the fabrication of integrated devices. The effect of diffusion rate, nature of the metal ion, and the catalytic reduction of the metal ions on the properties of the resulting hybrid graphene materials will be probed by Raman spectroscopy, surface-enhanced Raman Scattering Spectroscopy (SERS) and tip-enhanced Raman scattering spectroscopy (TERS).
Charge Extraction from Graphene with Adsorbed Charge-Transfer Organic Molecules
Borja Peropadre, P. Jarillo-Herro, A. Aspuru-Guzik
In this work, we study the potential of harvesting charge transfer excitons from a graphene monolayer. As an isolated material, graphene behaves as a gapless semiconductor, limiting its potential applications in future electronic devices. We circumvent this problem by chemically doping the graphene monolayer with flat organic molecules, such as perylenes and their derivatives. The planar nature of conjugated organic molecules will facilitate large electronic coupling and therefore allow for the efficient extraction of hot-carrier excitations in a time much faster than the typical exciton relaxation rate. An immediate application of this research project would be the fabrication and characterization of graphene-based photovoltaic devices which could eventually beat the Shockley-Queisser limit.
Yong Cheol Shin
The Effects of the Transfer Process on the Quality of CVD Graphene
Yong Cheol Shin, Roman Caudillo, Alan Logan, Mildred Dresselhaus, and Jing Kong
Currently, large-area monolayer graphene can be obtained via chemical vapor deposition using Cu foil as a growth substrate. Afterwards, the graphene needs to be transferred off from the Cu substrate in order to be used in most applications. However, the transfer process quite often unavoidably affects the properties of graphene, such as causing doping or introducing defects. It is very important to minimize such effects as much as possible for further applications. In order to do this, a clear understanding on the effects from the transfer process, ideally de-convoluted from the result of CVD growth is desirable. In this work, we investigated the effects of substrate treatment, cleaning process and graphene top surface passivation, using mechanically exfoliated graphene as a comparison.
Fabrication of High Quality of Graphene Sample
Senait Tesfamariam, Robert M. Westervelt
Two-dimensional (2D) crystalline materials have recently been identified and analyzed. The first material in this new class is graphene, a single atomic layer of carbon. This new material has a number of unique properties, which makes it interesting for both fundamental studies and future applications. The electronic properties of this 2D- material leads to, for instance, an unusual quantum hall effect it is a transparent conductor which is one atom thin. It also gives rise to analogies with particle physics. In addition graphene has a number of remarkable mechanical and electrical properties. It is substantially stronger than steel, and it is very stretchable. The thermal and electrical conductivity is very high and it can be used as a flexible conductor.
Heteroepitaxial Growth of Graphene by Way of Copper Initialization
Amber Wingfield, Gary L. Harris, James Griffin
Graphene is the formation of carbon atoms into a sheet like structure that is one atomic layer thick. Previous research has shown that graphene’s high electron mobility, flexibility, and transparency makes it a perfect candidate to bring semiconductor technology and the electronic device industries into a new age. A current and reliable method to acquiring graphene is through epitaxial growth on top of transition metals, such as copper and nickel, by way of chemical vapor deposition (CVD). However, in order to use this graphene on other substrates, a tedious and at times imperfect transfer process must take place. In efforts to improve the overall epitaxial growth method of graphene, the concept of forming this material directly onto a desired substrate (e.g. silicon or silicon dioxide) is explored. The constructed process will incorporate the use of a copper rich environment as a catalyst, to promote the nucleation of graphene on the non-metallic substrate. The end result is in hopes of eliminating the transfer process and is sought to fall within the current techniques and procedures of silicon technology.
Far-Infrared Graphene Plasmonic Crystals for Plasmonic Band Engineering
Kitty Yeung, Donhee Ham
Plasmons in graphene have been an attractive feature due to sub-wavelength confinement and tunability. A useful method to excite graphene plasmons is to pattern a graphene sheet into specific shapes, which allow phase matching between the plasmon modes and the incident radiation. Earlier efforts have relied on exciting localized plasmons in isolated graphene islands, such as ribbons, disks and rings. The geometry and dimensions of the islands determine the boundary conditions that define the localized plasmonic resonance frequency. An additional mechanism to control the localized plasmonic resonance frequency is to use electrostatic coupling between proximate islands, suggesting a principle of engineering wave dynamics via medium periodicity. We apply this principle in the presented work. In contrast to previous work, we introduce graphene plasmonic crystals in which delocalized plasmons are excited in a continuous graphene medium with a periodic structural perturbation, creating plasmonic bands in a manner akin to photonic crystals. Fourier transform infrared spectroscopy is used to demonstrate the plasmonic band formation. By measuring the extinction spectra of the graphene plasmonic crystals, we show that the incident far-infrared light resonantly couples to plasmonic modes that belong to a specific set of plasmonic bands. These specific bands are selected because their spatial symmetry, interpreted via group theory, matches that of the free-space radiation field. Adjusting the periodic geometry thus allows manipulation of the plasmonic bands. Further tuning of the plasmonic band frequencies is achieved by chemically doping charge carriers with HNOÂ¬3 vapor. Our work is a step toward graphene plasmonic band engineering, which may lead a new class of sub-wavelength graphene plasmonic devices, such as band gap filters, modulators, switches and metamaterials.
High-performance WSe2 CMOS Devices and Integrated Circuits
Lili Yu, Ahmad Zubair, Tomas Palacios
Two-dimensional (2D) crystals, including graphene, hexagonal boron nitride and transition metal dichalcogenides (TMD) materials, have outstanding properties for developing the next generation of electronic devices because of the excellent electrostatic control of the channel associated to their atomically thin structure. In addition, their mechanical strength and transparency makes them excellent candidates for transparent flexible electronics. For many of these applications, the realization of complementary metal-oxide-semiconductor (CMOS) logic is crucial to get high performance integrated circuits. CMOS logic has high noise immunity, low static power consumption and high density of integration. So far, complementary logic circuits have only been demonstrated on heterostructures of different layered materials with gain less than 2 and zero noise margin, . In this work, we demonstrate both pMOS and nMOS technologies on exfoliated WSe2, and we use them to fabricate monolithic CMOS integrated logic inverters with rail-to-rail logic operation, small power dissipation, large noise margin and voltage gain.