Excitonic Luminescence Upconversion in a Two-dimensional Semiconductor

Excitonic Luminescence Upconversion in a Two-dimensional Semiconductor PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

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Book Description
Photon upconversion is an elementary light-matter interaction process in which an absorbed photon is re-emitted at higher frequency after extracting energy from the medium. Furthermore, this phenomenon lies at the heart of optical refrigeration in solids(1), where upconversion relies on anti-Stokes processes enabled either by rare-earth impurities(2) or exciton-phonon coupling(3). We demonstrate a luminescence upconversion process from a negatively charged exciton to a neutral exciton resonance in monolayer WSe2, producing spontaneous anti-Stokes emission with an energy gain of 30 meV. Polarization-resolved measurements find this process to be valley selective, unique to monolayer semiconductors(4). Since the charged exciton binding energy(5) closely matches the 31 meV A(1)' optical phonon(6-9), we ascribe the spontaneous excitonic anti-Stokes to doubly resonant Raman scattering, where the incident and outgoing photons are in resonance with the charged and neutral excitons, respectively. Additionally, we resolve a charged exciton doublet with a 7 meV splitting, probably induced by exchange interactions, and show that anti-Stokes scattering is efficient only when exciting the doublet peak resonant with the phonon, further confirming the excitonic doubly resonant picture.

Excitonic Luminescence Upconversion in a Two-dimensional Semiconductor

Excitonic Luminescence Upconversion in a Two-dimensional Semiconductor PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 5

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Book Description
Photon upconversion is an elementary light-matter interaction process in which an absorbed photon is re-emitted at higher frequency after extracting energy from the medium. Furthermore, this phenomenon lies at the heart of optical refrigeration in solids(1), where upconversion relies on anti-Stokes processes enabled either by rare-earth impurities(2) or exciton-phonon coupling(3). We demonstrate a luminescence upconversion process from a negatively charged exciton to a neutral exciton resonance in monolayer WSe2, producing spontaneous anti-Stokes emission with an energy gain of 30 meV. Polarization-resolved measurements find this process to be valley selective, unique to monolayer semiconductors(4). Since the charged exciton binding energy(5) closely matches the 31 meV A(1)' optical phonon(6-9), we ascribe the spontaneous excitonic anti-Stokes to doubly resonant Raman scattering, where the incident and outgoing photons are in resonance with the charged and neutral excitons, respectively. Additionally, we resolve a charged exciton doublet with a 7 meV splitting, probably induced by exchange interactions, and show that anti-Stokes scattering is efficient only when exciting the doublet peak resonant with the phonon, further confirming the excitonic doubly resonant picture.

2D Excitonic Materials and Devices

2D Excitonic Materials and Devices PDF Author:
Publisher: Elsevier
ISBN: 0443193932
Category : Science
Languages : en
Pages : 270

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Book Description
Semiconductors and Semimetals series, highlights new advances in the field, with this new volume presenting interesting chapters. Each chapter is written by an international board of authors. Provides the latest information on cancer research Offers outstanding and original reviews on a range of cancer research topics Serves as an indispensable reference for researchers and students alike

Two-Dimensional Transition-Metal Dichalcogenides

Two-Dimensional Transition-Metal Dichalcogenides PDF Author: Alexander V. Kolobov
Publisher: Springer
ISBN: 3319314505
Category : Technology & Engineering
Languages : en
Pages : 545

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Book Description
This book summarizes the current status of theoretical and experimental progress in 2 dimensional graphene-like monolayers and few-layers of transition metal dichalcogenides (TMDCs). Semiconducting monolayer TMDCs, due to the presence of a direct gap, significantly extend the potential of low-dimensional nanomaterials for applications in nanoelectronics and nano-optoelectronics as well as flexible nano-electronics with unprecedented possibilities to control the gap by external stimuli. Strong quantum confinement results in extremely high exciton binding energies which forms an interesting platform for both fundamental studies and device applications. Breaking of spatial inversion symmetry in monolayers results in strong spin-valley coupling potentially leading to their use in valleytronics. Starting with the basic chemistry of transition metals, the reader is introduced to the rich field of transition metal dichalcogenides. After a chapter on three dimensional crystals and a description of top-down and bottom-up fabrication methods of few-layer and single layer structures, the fascinating world of two-dimensional TMDCs structures is presented with their unique atomic, electronic, and magnetic properties. The book covers in detail particular features associated with decreased dimensionality such as stability and phase-transitions in monolayers, the appearance of a direct gap, large binding energy of 2D excitons and trions and their dynamics, Raman scattering associated with decreased dimensionality, extraordinarily strong light-matter interaction, layer-dependent photoluminescence properties, new physics associated with the destruction of the spatial inversion symmetry of the bulk phase, spin-orbit and spin-valley couplings. The book concludes with chapters on engineered heterostructures and device applications such as a monolayer MoS2 transistor. Considering the explosive interest in physics and applications of two-dimensional materials, this book is a valuable source of information for material scientists and engineers working in the field as well as for the graduate students majoring in materials science.

Quantum Confined Excitons in 2-Dimensional Materials

Quantum Confined Excitons in 2-Dimensional Materials PDF Author: Carmen Palacios-Berraquero
Publisher: Springer
ISBN: 3030014827
Category : Computers
Languages : en
Pages : 125

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Book Description
This book presents the first established experimental results of an emergent field: 2-dimensional materials as platforms for quantum technologies, specifically through the optics of quantum-confined excitons. It also provides an extensive review of the literature from a number of disciplines that informed the research, and introduces the materials of focus – 2d Transition Metal Dichalcogenides (2d-TMDs) – in detail, discussing electronic and chemical structure, excitonic behaviour and response to strain. This is followed by a brief overview of quantum information technologies, including concepts such as single-photon sources and quantum networks. The methods chapter addresses quantum optics techniques and 2d-material processing, while the results section shows the development of a method to deterministically create quantum dots (QDs) in the 2d-TMDs, which can trap single-excitons; the fabrication of atomically thin quantum light-emitting diodes to induce all-electrical single-photon emission from the QDs, and lastly, the use of devices to controllably trap single-spins in the QDs –the first step towards their use as optically-addressable matter qubits.

Semiconductor Quantum Science and Technology

Semiconductor Quantum Science and Technology PDF Author:
Publisher: Academic Press
ISBN: 0128237740
Category : Science
Languages : en
Pages : 484

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Book Description
Semiconductor quantum science and technology is exploring the exciting and emerging prospects of integrating quantum functionality on semiconductor platforms to convert current information technology into quantum information technology. The past twenty years have led to incredible advances in this field. This book brings together the leading scientists who present the main achievements and challenges by reviewing and motivating the state-of-the-art at a tutorial level. The key challenges include creating quantum-light sources, quantum information processing via strong light-matter interaction, discovering new quantum materials as well as quasiparticles, and determining new quantum spectroscopic methodologies for superior control of quantum phenomena. As an important step, integration of these solutions on a semiconductor chip is discussed, and outlook for the future of semiconductor quantum science and technology is given. Leading experts present their vision on semiconductor quantum science and technology All aspects needed to realize semiconductor quantum science and technology are explained Quantum semiconductors from overviewed a tutorial introduction to the state-of-the-art

Ultrafast Spectroscopy of Semiconductors and Semiconductor Nanostructures

Ultrafast Spectroscopy of Semiconductors and Semiconductor Nanostructures PDF Author: Jagdeep Shah
Publisher: Springer Science & Business Media
ISBN: 366203770X
Category : Science
Languages : en
Pages : 536

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Book Description
Ultrafast spectroscopy of semiconductors and semiconductor nanostructures is currently one of the most exciting areas of research in condensed-matter physics. Remarkable recent progress in the generation of tunable femtosecond pulses has allowed direct investigation of the most fundamental dynamical processes in semiconductors. This second edition presents the most striking recent advances in the techniques of ultrashort pulse generation and ultrafast spectroscopy; it discusses the physics of relaxation, tunneling and transport dynamics in semiconductors and semiconductor nanostructures following excitation by femtosecond laser pulses.

Ultrafast Photonics

Ultrafast Photonics PDF Author: A. Miller
Publisher: CRC Press
ISBN: 0429524935
Category : Science
Languages : en
Pages : 325

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Book Description
Ultrafast photonics has become an interdisciplinary topic of high international research interest because of the spectacular development of compact and efficient lasers producing optical pulses with durations in the femtosecond time domain. Present day long-haul telecommunications systems are almost entirely based on the transmission of short burst

Optical Refrigeration

Optical Refrigeration PDF Author: Richard I. Epstein
Publisher: John Wiley & Sons
ISBN: 3527628053
Category : Science
Languages : en
Pages : 258

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Book Description
Edited by the two top experts in the field with a panel of International contributors, this is a comprehensive up-to-date review of research and applications. Starting with the basic physical principles of laser cooling of solids, the monograph goes on to discuss the current theoretical issues being resolved and the increasing demands of growth and evaluation of high purity materials suitable for optical refrigeration, while also examining the design and applications of practical cryocoolers. An advanced text for scientists, researchers, engineers, and students (masters, PHDs and Postdoc) in laser and optical material science, and cryogenics.

Semiconductor Photonics of Nanomaterials and Quantum Structures

Semiconductor Photonics of Nanomaterials and Quantum Structures PDF Author: Arash Rahimi-Iman
Publisher: Springer Nature
ISBN: 303069352X
Category : Science
Languages : en
Pages : 288

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Book Description
This book introduces the wider field of functional nanomaterials sciences, with a strong emphasis on semiconductor photonics. Whether you are studying photonic quantum devices or just interested in semiconductor nanomaterials and their benefits for optoelectronic applications, this book offers you a pedagogical overview of the relevant subjects along with topical reviews. The book discusses different yet complementary studies in the context of ongoing international research efforts, delivering examples from both fundamental and applied research to a broad readership. In addition, a hand-full of useful optical techniques for the characterization of semiconductor quantum structures and materials are addressed. Moreover, nanostructuring methods for the production of low-dimensional systems, which exhibit advantageous properties predominantly due to quantum effects, are summarized. Science and engineering professionals in the interdisciplinary domains of nanotechnology, photonics, materials sciences, and quantum physics can familiarize themselves with selected highlights with eyes towards photonic applications in the fields of two-dimensional materials research, light–matter interactions, and quantum technologies.

Chemical Abstracts

Chemical Abstracts PDF Author:
Publisher:
ISBN:
Category : Chemistry
Languages : en
Pages : 2626

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Book Description