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Related papers: Population inversion in Landau-quantized graphene

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Could a laser field lead to the much sought-after tunable bandgaps in graphene? By using Floquet theory combined with Green's functions techniques, we predict that a laser field in the mid-infrared range can produce observable bandgaps in…

Mesoscale and Nanoscale Physics · Physics 2011-06-10 Hernan L. Calvo , Horacio M. Pastawski , Stephan Roche , Luis E. F. Foa Torres

Consider the quantum evolution of a charged particle subjected to a uniform magnetic field and an electric field E(t) that exists for a finite period of time. The electric field can induce intra-Landau level transitions (magnetic…

Quantum Physics · Physics 2011-12-20 James Chee , Yu-Hua Zhang

We study nonlinear optical response of graphene in the quantum Hall regime to an intense laser pulse. In particular, we consider harmonic generation process. We demonstrate that the generalized magneto-optical conductivity of graphene on…

Mesoscale and Nanoscale Physics · Physics 2016-11-01 H. K. Avetissian , G. F. Mkrtchian

A partially filled Landau level (LL) hosts a variety of correlated states of matter with unique properties. The ability to control these phases requires tuning the effective electron interactions within a LL, which has been difficult to…

Mesoscale and Nanoscale Physics · Physics 2011-12-20 Z. Papić , D. A. Abanin , Y. Barlas , R. N. Bhatt

The inter-Landau level transitions observed in far-infrared transmission experiments on few-layer graphene samples show a behaviour characteristic of the linear dispersion expected in graphene. This behaviour persists in relatively thick…

Materials Science · Physics 2009-11-13 M. L. Sadowski , G. Martinez , M. Potemski , C. Berger , W. A. de Heer

Unlike in ordinary metals, in graphene, phonon structure can be seen in the quasiparticle electronic density of states, because the latter varies on the scale of the phonon energy. In a magnetic field, quantization into Landau levels…

Mesoscale and Nanoscale Physics · Physics 2015-05-28 Adam Pound , J. P. Carbotte , E. J. Nicol

We study population distributions and lasing actions of N_2^+ driven by femtosecond lasers with various wavelengths, and uncover an efficient ionic excitation mechanism induced by synchronized ionization and multiphoton resonance. Our…

Using the $\alpha$-T$_3$ model, we carried out analytical and numerical calculations for the static and dynamic polarization functions in the presence of a perpendicular magnetic field. These results were employed to determine the…

Mesoscale and Nanoscale Physics · Physics 2021-02-17 Antonios Balassis , Dipendra Dahal , Godfrey Gumbs , Andrii Iurov , Danhong Huang , Oleksiy Roslyak

Magnetic effects at optical frequencies are notoriously weak. This is evidenced by the fact that the magnetic permeability of nearly all materials is unity in the optical frequency range, and that magneto-optical devices (such as Faraday…

Mesoscale and Nanoscale Physics · Physics 2015-06-05 Mikael C. Rechtsman , Julia M. Zeuner , Andreas Tünnermann , Stefan Nolte , Mordechai Segev , Alexander Szameit

The ability to tune the wavelength of light emission on a silicon chip is important for scalable photonic networks, distributed photonic sensor networks and next generation computer architectures. Here we demonstrate light emission in a…

The magneto-optical properties of bilayer phosphorene is investigated by the generalized tight-binding model and the gradient approximation. The vertical inter-Landau-level transitions, being sensitive to the polarization directions, are…

Mesoscale and Nanoscale Physics · Physics 2018-01-09 Jhao-Ying Wu , Szu-Chao Chen , Thi-Nga Do , Wu-Pei Su , Godfrey Gumbs

We theoretically study a superradiant laser, deriving both the steady-state behaviors and small-amplitude responses of the laser's atomic inversion, atomic polarization, and light field amplitude. Our minimum model for a three-level laser…

Atomic Physics · Physics 2014-01-15 Justin G. Bohnet , Zilong Chen , Joshua M. Weiner , Kevin C. Cox , James K. Thompson

Bilayer graphene provides a unique platform to explore the rich physics in quantum Hall effect. The unusual combination of spin, valley and orbital degeneracy leads to interesting symmetry broken states with electric and magnetic field.…

Mesoscale and Nanoscale Physics · Physics 2019-03-27 Manabendra Kuiri , Anindya Das

Gaseous ammonia has previously been demonstrated as a compelling gain medium for a quantum cascade laser pumped molecular laser (QPML), exhibiting good power efficiency but limited tunability. Here we explore the potential of the ammonia…

We present a detailed numerical investigation of the tunability of a diffusive random laser when Mie resonances are excited. We solve a multimode diffusion model and calculate multiple light scattering in presence of optical gain which…

Optics · Physics 2015-06-23 Michele Gaio , Matilda Peruzzo , Riccardo Sapienza

We investigate the nonlinear Compton photon source for upcoming laser-particle experiments in the collision scenario of high-energy electron beams and relativistic laser pulses. The stronger laser field could not only improve the scattering…

High Energy Physics - Phenomenology · Physics 2025-05-23 Yu Xin , Zu-dong Zhao , Suo Tang

We develop a theoretical framework for Landau levels in quasi-periodic twisted bilayer graphene at a $30^\circ$ twist angle, a system without translational symmetry but possessing 12-fold rotational symmetry. Using a quasi-band formalism,…

Mesoscale and Nanoscale Physics · Physics 2026-04-22 Masaru Hitomi , Takuto Kawakami , Mikito Koshino

Broadband wavelength tuneability can ensure a new level of versatility for laser systems and extend areas of their applications. Principle limitations of achieving wide tuning wavelength ranges are generally defined by the spectral…

We study plasmon modes in doped AA-stacked bilayer graphene (BLG) within the nearest-neighbor tight-binding and the random phase approximation. We obtain closed analytical expressions for the polarizability function which are used to obtain…

Mesoscale and Nanoscale Physics · Physics 2022-12-09 Yawar Mohammadi

We experimentally study a fiber loop laser in the Figure-8 configuration, and explore the dependency of the degree of polarization on controlled parameters. To account for the experimental observations, a mapping is derived to evaluate the…

Optics · Physics 2024-06-19 Banoj Kumar Nayak , Cijy Mathai , Dmitry Panna , Eyal Buks