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Related papers: Population inversion in Landau-quantized graphene

200 papers

We present a comprehensive study of the band structure of two- and three-dimensional hexagonal layered materials using Landau Level optical Hall effect spectroscopy investigations, employing graphene and graphite as model systems. We study…

Materials Science · Physics 2017-05-24 Philipp Kühne , Vanya Darakchieva , Mathias Schubert

Landau level spectroscopy plays an important role in modern condensed-matter physics. In this technique, electrons in a solid are subjected to quantizing magnetic fields and probed experimentally, often through optical methods. Direct and…

Materials Science · Physics 2026-05-12 Ana Akrap , Milan Orlita

Monolayer graphene provides an ideal material to explore one of the fundamental light-field driven interference effects: Landau-Zener-St\"uckelberg interference. However, direct observation of the resulting interference patterns in momentum…

Mesoscale and Nanoscale Physics · Physics 2021-02-10 Q. Z. Li , P. Elliott , J. K. Dewhurst , S. Sharma , S. Shallcross

Graphene plasmons have recently attracted a great deal of attention because of their tunability, long lifetime, and high degree of field confinement in the vertical direction. Nearby metal gates have been shown to modify the graphene…

Mesoscale and Nanoscale Physics · Physics 2018-08-01 Alessandro Principi , Erik van Loon , Marco Polini , Mikhail I. Katsnelson

The influence of photon-momentum recoil on adiabatic population transfer in an atomic three-level lambda system is studied. It is shown that the Doppler frequency shifts, due to atomic motion can play an important role in adiabatic…

Quantum Physics · Physics 2016-11-03 R. G. Unanyan

Time-resolved optical measurements of electron spin dynamics in modulation doped InGaAs quantum wells are used to explore electron spin coherence times and spin precession frequencies in a regime where an out of plane magnetic field…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 V. Sih , W. H. Lau , R. C. Myers , A. C. Gossard , M. E. Flatté , D. D. Awschalom

We investigate the arising of an analogue of the Landau quantization from a background of the violation of the Lorentz symmetry established by a time-like 4-vector and a field configuration of crossed electric and magnetic field. We also…

High Energy Physics - Theory · Physics 2015-07-21 K. Bakke , H. Belich

A method for solving the problem of efficient population transfer from the ground to some excited state by available technical means (varying resonator length) is proposed. We consider a mixture of similar quantum systems distributed in a…

Quantum Physics · Physics 2023-12-04 K. A. Lyakhov , A. N. Pechen

We experimentally investigate generation of backward 357 nm N2 laser in a gas mixture of N2/Ar using 800-nm femtosecond laser pulses, and examine the involved gain dynamics based on pump-probe measurements. Our findings show that a minimum…

Optics · Physics 2015-04-09 Hongqiang Xie , Guihua Li , Wei chu , Bin Zeng , Jinping Yao , Chenrui Jing , Ziting Li , Ya Cheng

Landau level broadening mechanisms in electrically neutral and quasineutral graphene were investigated through micro-magneto-Raman experiments in three different samples, namely, a natural single-layer graphene flake and a back-gated…

We present theoretical and experimental results of coherent population trapping spectra on a multi-level $^{40}$Ca$^+$-type configuration, adding a third beam to the standard two-laser $\Lambda$ system to avoid undesired optical pumping. We…

Quantum Physics · Physics 2022-11-15 Nicolás Nuñez Barreto , Martin Drechsler , Christian Tomás Schmiegelow

The microbunching instability has been a long-standing issue for high-brightness free-electron lasers (FELs), and is a significant show-stopper to achieving full longitudinal coherence in the x-ray regime. This paper reports the first…

We present experimental results demonstrating controllable dispersion in a ring laser by monitoring the lasing-frequency response to cavity-length variations. Pumping on an N-type level configuration in ${}^{87}$Rb, we tailor the…

We investigate, analytically and numerically, the effects of disorder on the density of states and on the localization properties of the relativistic two dimensional fermions in the lowest Landau level. Employing a supersymmetric technique,…

Mesoscale and Nanoscale Physics · Physics 2007-11-08 Pallab Goswami , Xun Jia , Sudip Chakravarty

When charge transport occurs under conditions like topological protection or ballistic motion, the conductance of low-dimensional systems often exhibits quantized values in units of $e^{2}/h$, where $e$ and $h$ are the elementary charge and…

Mesoscale and Nanoscale Physics · Physics 2024-12-05 Baojuan Dong , Kai Zhao , Kenji Watanabe , Takashi Taniguchi , Jianming Lu , Jianting Zhao , Fengcheng Wu , Jing Zhang , Zheng Han

We study the interplay between a Kekul\'e patterned distortion in monolayer graphene and a monochromatic laser irradiation, focusing in the long wavelength approximation of its Landau level structure. Exploiting the symmetries of the…

Mesoscale and Nanoscale Physics · Physics 2023-03-06 A. López , F. Mireles

Injection or optical generation of electrons and holes in graphene bilayers (GBLs) can result in the interband population inversion enabling the terahertz (THz) radiation lasing. The intraband radiative processes compete with the interband…

Mesoscale and Nanoscale Physics · Physics 2015-08-21 V. Ryzhii , M. Ryzhii , V. Mitin , M. S. Shur , T. Otsuji

A new method is proposed to produce population inversion on transitions involving the ground state of atoms. The method is realized experimentally with sodium atoms. Lasing at the frequency corresponding to the sodium D_2 line is achieved…

We calculate the static polarization of AAA-stacked trilayer graphene (TLG) and study its screening properties within the random phase approximation (RPA) in all undoped, doped and biased regimes. We find that the static polarization of…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Yawar Mohammadi , Rostam Moradian , Farzad Shirzadi Tabar

Recent studies on cavity-coupled two-dimensional electron gas demonstrate that vacuum-field engineering can tailor electronic transport properties of materials. By achieving ultra-strong coupling between a terahertz resonator and mesoscopic…