Leuenberger Nano Lab

Michael N. Leuenberger, Ph.D.

Selected Publications

  1. Alireza Safaei, Sayan Chandra, Muhammad Waqas Shabbir, Michael N. Leuenberger, Debashis Chanda, Dirac plasmon-assisted asymmetric hot carrier generation for room-temperature infrared detection, Nature Communications 10, 3498 (2019). We demonstrate theoretically and experimentally that the plasmon-assisted photothermoelectric effect in asymmetrically nanopatterned graphene can be used to detect mid-IR light with detectivity of D*=109 J at room temperature.
  2. Chandriker K. Dass, M. A. Khan, Genevieve Clark, Je_rey A. Simon, Michael N. Leuenberger, Ricky Gibson, Shin Mou, Xiaodong Xu, Joshua R. Hendrickson, Ultra-Long Lifetimes of Defect Trapped Single Quantum Emitters in Monolayer WSe2/hBN Heterostructures, Adv. Quantum Technol. 2, 1900022 (2019). We show theoretically and experimentally identify possible candidates for the defects in monolayer WSe2 that can be used a single-photon emitters with ultra-long lifetimes.
  3. Alireza Safaei, Sayan Chandra, Michael N. Leuenberger, Debashis Chanda, Wide Angle Dynamically Tunable Enhanced Infrared Absorption on Large-Area Nanopatterned Graphene, ACS Nano 13, 421 (2019). We show theoretically and experimentally that nanopatterned graphene exhibits strong mid-IR light absorption at wide angles of incidence.
  4. M. A. Khan, Michael N. Leuenberger, Room-temperature superparamagnetism due to giant magnetic anisotropy in MoS defected single layer MoS2, J. Phys.: Condens. Matter 30, 155802 (2018). We show theoretically that MoS defects in MoS2 exhibit a large magnetic moment with a giant magnetic anisotropy.
  5. Mahtab A. Khan, Mikhail Erementchouk, J. Hendrickson, Michael N. Leuenberger, Electronic and optical properties of vacancy defects in single-layer transition metal dichalcogenides, Phys. Rev. B 95, 245435 (2017). We theoretically characterized the bound states of vacancy defects and their optical properties in a variety of transition metal dichalcogenides.
  6. Mikhail Erementchouk, M. A. Khan, Michael N. Leuenberger, Optical signatures of states bound to vacancy defects in monolayer MoS2, Phys. Rev. B Rapid Communications 92, 075439(R) (2015). We theoretically characterized the bound states of vacancy defects and their optical properties in MoS2.
  7. Alireza Safaei, S. Chandra, A. Vazquez-Guardado, J. Calderon, D. Franklin, L. Tetard, L. Zhai, Michael N. Leuenberger, D. Chanda, Dynamically tunable extraordinary light absorption in monolayer graphene, Phys. Rev. B 96, 165431 (2017). We show that nanopatterned graphene exhibits an extraordinarily large absorption compared to pristine graphene.
  8. Muhammad R. Islam, Narae Kang, Udai Bhanu, Hari P. Paudel, Mikhail Erementchouk, Laurene Tetard, Michael N. Leuenberger, Saiful I. Khondaker, Tuning the electrical property via defect engineering of single layer MoS2 by oxygen plasma, Nanoscale 6, 10033 (2014). This work proposes a new method to tune the conductivity of a single layer of MoS2 using oxygen plasma exposure.
  9. Hari P. Paudel, Michael N. Leuenberger, Three-dimensional topological insulator quantum dot for optically controlled quantum memory and quantum computing, Phys. Rev. B 88, 085316 (2013). Here we propose a novel method to implement optically mediated quantum memory and quantum computing with quantum dots made of 3D topological insulator material. The optical control is based on the classical and single-photon Faraday rotation due to the Pauli exclusion principle. We show that this effect is large for surfaces of 3D topological insulators and also for quantum dots made of 3D topological insulator material.
  10. Hari P. Paudel, Michael N. Leuenberger, Light-controlled plasmon switching using hybrid metal-semiconductor nanostructures, Nano Lett. 12, 2690 (2012). Here we propose a novel switching mechanism for controlling the propagation of surface plasmon polaritons (SPPs) through a chain of Ag-GaN core-shell nanoparticles, where the switching sites are replaced by Ag-TiO2 core-shell nanoparticles. The main idea is to excite electron-hole pairs inside TiO2, which changes the index of refraction
  11. Sergio Tafur, Michael N. Leuenberger, Single Photon Near Field Emission and Revival in Quantum Dots, Rev. Nanosci. Nanotechnol. 1, 152-161 (2012) and Proc. SPIE 8057, 805704 (2011). In this work we describe the spontaneous emission of a single photon from a single quantum dot by means of the single photon wave function. We obtain analytically three poles that lead to new near-field revival phenomena. The frequencies/poles of these near-field oscillations correspond to the energy uncertainty due to the localization of the energy inside the quantum dot.
  12. Mikhail Erementchouk, Michael N. Leuenberger, Complex dynamics of photon entanglement in the two-mode Jaynes–Cummings model, Nanotechnology 21, 274019 (2010). This work demonstrates that the interaction of many photons with a single quantum dot inside a nanocavity yields highly entangled many-photon states, which can be used for entangled many-photon sources.
  13. M. Erementchouk, M. N. Leuenberger, Entanglement of photons due to nonlinear response of quantum wells, Phys. Rev. B 81, 195308 (2010). Here we propose a method to create entangled photons with high efficiency using the many-body correlations among excitons in a quantum well.
  14. H. P. Seigneur, Michael N. Leuenberger, Winston V. Schoenfeld, Single photon Mach-Zehnder interferometer for quantum networks based on the Single Photon Faraday Effect, J. Appl. Phys. 104, 014307 (2008). This work describes the novel concept of using the conditional single-photon Faraday rotation to perform single-qubit gates on the polarization degree of freedom for photons by means of a Mach-Zehnder interferometer.
  15. G. Gonzalez, M. N. Leuenberger, Berry-phase blockade in single-molecule magnets, Phys. Rev. Lett. 98, 256804 (2007). This paper demonstrates single-electron transistor (SET) effects in the Coulomb blockade regime for the quantum transport through molecular magnets. In particular, it is shown that the topological Berry-phase interference effect leads to a Berry-phase blockade of the current through a single-molecule magnet.
  16. M. Erementchouk, M. N. Leuenberger, and L. J. Sham, Many-body interaction in semiconductor probed with 2D Fourier spectroscopy, Phys. Rev. B 76, 115307 (2007). In this work we provided a microscopic theory that links the measured peaks in the 2D Fourier spectroscopy with the many-body correlations, thereby distinguishing clearly between quantum statistical and Coulomb effects.
  17. M. N. Leuenberger, Fault-tolerant quantum computing with spins using the conditional Faraday rotation, Phys. Rev. B 73, 075312 (2006). This paper is the basis for quantum computing proposed in the project on the quantum network inside a photonic crystal.
  18. M. N. Leuenberger, M. E. Flatté, D. D. Awschalom, Teleportation of electronic many-qubit states via single photons, Phys. Rev. Lett. 94, 107401 (2005). This paper is the basis for quantum teleportation proposed in the project on the quantum network based on semiconductor quantum dots inside a photonic crystal.
  19. M. N. Leuenberger, D. Loss, Quantum Computing in Molecular Magnets, Nature 410, 789-793 (2001). We show an electron spin resonance technique to implement quantum computing in molecular magnets.

Book Chapters

  1. Mikhail Erementchouk, Volodymyr Turkowski, Michael N. Leuenberger, Quantum Field Theory of Exciton Correlations and Entanglement in Semiconductor Structures, Advances in Quantum Field Theory, Edited by Sergey Ketov (Intech, 2012). This book chapter provides an overview over our recent progress in describing many-body correlations and entanglement among excitons in semiconductor structures.
  2. Gabriel González, Michael N. Leuenberger, Quantum Computing in Spin Nano-Systems, invited book chapter, Handbook of Nanophysics: Nanoelectronics and Nanophotonics, pages 1-1 to 1-22, Edited by Klaus D. Sattler (Taylor-Francis, 2010). This book chapter gives an overview over the theoretical work that has been done to propose condensed matter systems that could be used for the implementation of quantum computing with spin systems.
  3. Gabriel González, Michael N. Leuenberger, Quantum Spin Tunneling in Molecular Nanomagnets, invited book chapter, Handbook of Nanophysics: Nanoelectronics and Nanophotonics, pages 9-1 to 9-14, Edited by Klaus D. Sattler (Taylor-Francis, 2010). This book chapter gives an overview over the field of macroscopic quantum tunneling of the spin of single-molecule magnets and the application to quantum computing.
  4. Mikhail Erementchouk, Michael N. Leuenberger, Nonlinear Optics in Semiconductor Nanostructures, invited book chapter, Handbook of Nanophysics: Nanoelectronics and Nanophotonics, pages 29-1 to 29-20, Edited by Klaus D. Sattler (Taylor-Francis, 2010). This book chapter gives a quantum-field theoretical description of the bandstructure calculation of semiconductor nanostructures and the nonlinear optical effects, in particular 4-wave mixing

Patents

  1. Michael N. Leuenberger, Michael E. Flatte, David D. Awschalom, Teleportation System For Electronic Many-Qubit States Using Individual Photons, United States Patent, Patent No. US 7,667,995 B1, Date of Patent: Feb. 23, 2010.
  2. D. Chanda, A. Safaei, M. N. Leuenberger, Extraordinary Dynamically Tunable Absorption in Monolayer Graphene, United States Patent, Patent No. US 10,283,871, Date of Patent: June 4, 2019.
  3. D. Chanda, M. N Leuenberger, A. Safaei, S. Chandra, Plasmon-Assisted Photo-thermoelectric Effect-Based Detection of Infrared Radiation on Asymmetrically Patterned Graphene, US Patent App. 62/725,297, 2018.