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Related papers: Control of excitonic absorption by thickness varia…

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Significant excitonic effects were observed in graphene by measuring its optical conductivity in a broad spectral range including the two-dimensional {\pi}-band saddle-point singularities in the electronic structure. The strong…

Materials Science · Physics 2015-05-20 Kin Fai Mak , Jie Shan , Tony F. Heinz

Optical control of the lateral quantum confinement and number of electrons confined in nanofabricated GaAs/AlGaAs quantum dots is achieved by illumination with a weak laser beam that is absorbed in the AlGaAs barrier. Precise tuning of…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Sokratis Kalliakos , Vittorio Pellegrini , Cesar Pascual Garcia , Aron Pinczuk , Loren N. Pfeiffer , Ken. W. West

Reabsorption, the multiple scattering of spontaneously emitted photons in optically thick gases, is a major limitation to efficient optical pumping and laser cooling in ultracold gases. We report mitigation of reabsorption using spatial and…

Gate-controllable two dimensional systems with in-plane modulation of properties could serve as highly tunable effective media. Intuitively, such systems may bring novel functionality provided that the period of the lateral modulation is…

Mesoscale and Nanoscale Physics · Physics 2019-11-04 Alexey Shupletsov , Alexander Kuntsevich , Martin Nunuparov , Alexander Rakhmanov , Kirill Prikhodko

Strong Coulomb interaction in 2D materials provides unprecedented opportunities for studying many key issues of condensed matter physics, such as co-existence and mutual conversions of excitonic complexes, fundamental optical processes…

Mesoscale and Nanoscale Physics · Physics 2018-12-12 Zhen Wang , Hao Sun , Qiyao Zhang , Jiabin Feng , Jianxing Zhang , Yongzhuo Li , Cun-Zheng Ning

Due to the strong quantum confinement effect, few-layer {\gamma}-InSe exhibits a layer-dependent bandgap, spanning the visible and near infrared regions, and thus recently draws tremendous attention. As a two-dimensional material, the…

Mesoscale and Nanoscale Physics · Physics 2018-03-20 Chaoyu Song , Fengren Fan , Ningning Xuan , Shenyang Huang , Guowei Zhang , Chong Wang , Zhengzong Sun , Hua Wu , Hugen Yan

The strength of light-matter interaction is of central importance in photonics and optoelectronics. For many widely studied two-dimensional semiconductors, such as MoS2, the optical absorption due to exciton resonances increases with…

Mesoscale and Nanoscale Physics · Physics 2020-04-16 Guowei Zhang , Shenyang Huang , Fanjie Wang , Qiaoxia Xing , Chaoyu Song , Chong Wang , Yuchen Lei , Mingyuan Huang , Hugen Yan

Exciton dissociation via the excitonic Mott transition (EMT) governs the high-density optical response of semiconductors and sets fundamental limits for optoelectronic devices. The EMT is conventionally linked to the onset of population…

The extraordinary electronic and optical properties of the crystal-to-amorphous transition in phase-change materials led to important developments in memory applications. A promising outlook is offered by nanoscaling such phase-change…

We study the linear optical absorption of bulk semiconductors in the presence of a homogeneous constant (dc) electric field with an approach suitable for including excitonic effects while working with many-band models. The absorption…

Mesoscale and Nanoscale Physics · Physics 2015-06-19 Federico Duque-Gomez , J. E. Sipe

A simple analysis is performed for the absorption properties of graphene; sandwiched between two media. For a proper choice of media and graphene doping/gating one can approach 50-100% absorption in the GHz-THz range for the one atom thick…

Optics · Physics 2012-01-17 S. P. Apell , G. W. Hanson , C. Hägglund

We report significant changes of optical conductivity in single layer graphene induced by mild oxygen plasma exposure, and explore the interplay between carrier doping, disorder, and many-body interactions from their signatures in the…

Graphene is an ultrathin material, which allows us to control surface phenomena by means of field-effect gating. Among various surface phenomena, photo-oxidation is known to be a facile method to largely control the electronic structure of…

Materials Science · Physics 2020-02-06 Ryo Nouchi , Morihiro Matsumoto , Nobuhiko Mitoma

Renew interest in the charge density wave phase of TiSe$_2$ stems from the realization of its unique driving mechanism, the so called excitonic insulator phase. Existing claims are motivated by model calculations of the band structure. In…

Strongly Correlated Electrons · Physics 2024-08-13 Turgut Yilmaz , Anil Rajapitamahuni , Elio Vescovo

Excitonic fine structure splitting in quantum dots is closely related to the lateral shape of the wave functions. We have studied theoretically the fine structure splitting in InAs quantum dots with a type-II confinement imposed by a GaAsSb…

Mesoscale and Nanoscale Physics · Physics 2015-12-02 Vlastimil Křápek , Petr Klenovský , Tomáš Šikola

Over the past few years, there has been a growing interest in layered transition metal dichalcogenides (TMD) such as molybdenum disulfide (MoS2). Most studies so far have focused on the electronic and optoelectronic properties of…

Mesoscale and Nanoscale Physics · Physics 2016-10-03 Morteza Kayyalha , Jesse Maassen , Mark Lundstrom , Li Shi , Yong P. Chen

Controllable topological phase transitions are appealing as they allow for tunable single particle electronic properties. Here, by using state-of-the-art manybody perturbation theory techniques, we show that the topological $Z_2$ phase…

Mesoscale and Nanoscale Physics · Physics 2022-10-13 Davide Romanin , Matteo Calandra , Alex W. Chin

We examine the excitonic nature of high-lying optical transitions in single-walled carbon nanotubes by means of Rayleigh scattering spectroscopy. A careful analysis of the principal transitions of individual semiconducting and metallic…

Mesoscale and Nanoscale Physics · Physics 2010-01-27 Stephane Berciaud , Christophe Voisin , Hugen Yan , Bhupesh Chandra , Robert Caldwell , Yuyao Shan , Louis E. Brus , James Hone , Tony F. Heinz

We experimentally demonstrate the elementary case of electromagnetically induced transparency (EIT) with a single atom inside an optical cavity probed by a weak field. We observe the modification of the dispersive and absorptive properties…

Optical absorption is one of fundamental light-matter interactions. In most materials, optical absorption is a weak perturbation to the light. In this regime, absorption and emission are irreversible, incoherent processes due to strong…