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Search Publications by: Michael Gullans (Fed)

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Displaying 26 - 35 of 35

Observation of chiral photocurrent transport in the quantum Hall regime in graphene

May 24, 2021
Author(s)
Glenn S. Solomon, Olivier Gazzano, Bin Cao, Jiuning Hu, David B. Newell, Tobias Huber, Michael Gullans, Mohammad Hafezi, Tobias Grass
Optical excitation provides a powerful tool to investigate non-equilibrium physics in quantum Hall systems. Moreover, the length scale associated with photo-excited charge carries lies between that of local probes and global transport measurements. Here

Tunable three-body loss in a nonlinear Rydberg medium

May 5, 2021
Author(s)
James(Trey) Porto, Alexey Gorshkov, Michael Gullans, D. Ornelas-Huerta, Przemyslaw Bienias, A. Craddock, A. Hachtel, Marcin Kalinowski, Mary Lyon, Steven L. Rolston
Long-range Rydberg interactions, in combination with electromagnetically induced transparency(EIT), give rise to strongly interacting photons where the strength, sign, and form of the interactions are widely tunable and controllable. Such control can be

Entanglement and purification transitions in non-Hermitian quantum mechanics

April 30, 2021
Author(s)
Michael Gullans, Sarang Gopalakrishnan
A quantum system subject to continuous measurement and post-selection evolves according to a non- Hermitian Hamiltonian. We show that, as one increases the rate of post-selection, this non- Hermitian Hamiltonian can undergo a spectral phase transition. On

Photon thermalization via laser cooling of atoms

July 19, 2018
Author(s)
Chiao-Hsuan Wang, Michael Gullans, James V. Porto, William D. Phillips, Jacob Taylor
The cooling of atomic motion by scattered light enables a wide variety of technological and scientific explorations. Here we focus on laser cooling from the perspective of the light — specifi- cally, the scattering of light between different optical modes

Light-induced fractional quantum hall phases in graphene

December 15, 2017
Author(s)
Michael Gullans, Areg Ghazaryan, Pouyan Ghaemi, Mohammad Hafezi
We show how to realize two-component fractional quantum Hall phases in monolayer graphene by optically driving the system. A laser is tuned into resonance between two Landau levels of graphene and acts as a e ective tunneling term between these states. We

Valley blockade in a silicon double quantum dot

November 13, 2017
Author(s)
Justin K. Perron, Michael Gullans, Jacob Taylor, Michael Stewart, Neil M. Zimmerman
Electrical transport in double quantum dots (DQD) is useful for illuminating many interesting aspects of the carrier states in quantum dots. Here we show data comparing bias triangles (i.e., regions of allowed current in DQDs) at positive and negative bias

Coulomb bound states of strongly interacting photons

September 18, 2015
Author(s)
Mohammad F. Maghrebi, Michael Gullans, Przemek Bienias, Soonwon Choi, Ivar Martin, Ofer Firstenberg, Mikhail D. Lukin, Hans Peter Buchler, Alexey Gorshkov
We show that two photons coupled to Rydberg states via electromagnetically induced transparency can interact via an effective Coulomb potential. This interaction gives rise to a continuum of two-body bound states. Within the continuum, metastable bound

Quantum Nonlinear Optics Near Optomechanical Instabilities

January 9, 2015
Author(s)
Xunnong Xu, Michael Gullans, Jacob Taylor
Optomechanical systems provide a unique platform for observing quantum behavior of macro- scopic objects. However, efforts towards realizing nonlinear behavior at the single photon level have been inhibited by the small size of the radiation pressure