Prolonged photo-carriers generated in a massive-and-anisotropic Dirac material

Nurmamat, Munisa; Ishida, Y.; Yori, Ryohei; Sumida, Kazuki; Zhu, Siyuan; Nakatake, M.; Ueda, Y.; Takeuchi, Masaki; Shin, Shik; Akahama, Yuichi; Kimura, Akio

doi:10.1038/s41598-018-27133-6

Cited by 14 publications

(14 citation statements)

References 44 publications

(56 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…28, in agreement with resonant transient absorption measurements [29]. Although extensive theoretical work was done on 1L-and few-layers (FL) BP [5, 6, 10-12, 14, 18], ARPES measurements were only performed on bulk crystals cleaved in situ with no control on sample thickness [16,17,25,28,30]. The depth sensitivity of photoemission critically depends on the photon energy hν (it can range from 1L at hν ∼ 100eV to several nm at hν ∼ 6eV) [31].…”

supporting

confidence: 68%

Non-equilibrium band broadening, gap renormalization and band inversion in black phosphorus

et al. 2021

View full text Add to dashboard Cite

Black phosphorous (BP) is a layered semiconductor with high carrier mobility, anisotropic optical response and wide bandgap tunability. In view of its application in optoelectronic devices, understanding transient photo-induced effects is crucial. Here, we investigate by time- and angle-resolved photoemission spectroscopy BP in its pristine state and in the presence of Stark splitting, chemically induced by Cs ad-sorption. We show that photo-injected carriers trigger bandgap renormalization, and a concurrent valence band flattening caused by Pauli blocking. In biased samples, photo-excitation leads to a long-lived (ns) surface photovoltage of few hundreds mV that counterbalances the Cs-induced surface band bending. This allows us to disentangle bulk from surface electronic states, and to clarify the mechanism underlying the band inversion observed in bulk samples.

show abstract

supporting

confidence: 68%

Non-equilibrium band broadening, gap renormalization and band inversion in black phosphorus

et al. 2021

View full text Add to dashboard Cite

show abstract

“…This gives D 0 ∼ 10 cm 2 /s. Considering that the carrier lifetime in similar material is about τ R 400 ps [43], we find l D 0.6 µm. The capture velocity can be estimated in the range [36,37] C 0 ∼ 10 4 − 10 5 cm/s.…”

Section: Carrier Effective Temperature and Quasi-fermi Energies Vmentioning

confidence: 83%

Negative Terahertz Conductivity at Vertical Carrier Injection in a Black-Arsenic-Phosphorus–Graphene Heterostructure Integrated With a Light-Emitting Diode

Ryzhii

Otsuji

et al. 2019

IEEE J. Select. Topics Quantum Electron.

View full text Add to dashboard Cite

We propose and analyze the heterostructure comprising a black-arsenic-phosphorus layer (b-As1−xPxL) and a graphene layer (GL) integrated with a light-emitting diode (LED). The integrated b-As1−xPxL-GL-LED heterostructure can serve as an active part of the terahertz (THz) laser using the interband radiative transitions in the GL. The feasibility of the proposed concept is enabled by the combination of relatively narrow energy gap in the b-As1−xPxL and the proper band alignment with the GL. The operation of the device in question is associated with the generation of the electron-hole pairs by the LED emitted near-infrared radiation in the b-As1−xPxL, cooling of the photogenerated electrons and holes in this layer, and their injection into the GL. Since the minimum b-As1−xPL energy gap (∆G ≃ 0.15 eV) is smaller than the energy of optical phonons in the GL, ( ω0 ≃ 0.2 eV), the injection into the GL can lead to a relatively weak heating of the two-dimensional electron-hole plasma (2D-EHP) in the GL. At the temperatures somewhat lower than the room temperature, the injection can cool the 2D-EHP. This is beneficial for the interband population inversion in the GL, reinforcement of its negative dynamic conductivity, and the realization of the optical and plasmonic modes lasing supporting the new types of the THz radiation sources.

show abstract

“…The recent studies using trARPES on SrMnBi 2 [23] and black phosphorus [24] have shown that the excess electron energy shows a slow dynamics, that is, a power law decay just before reaching a thermal equilibrium. For the latter, an exciton effect on the electron relaxation has been suggested to explain the power law decay.…”

Section: B Trarpesmentioning

confidence: 99%

Modeling the nonthermal relaxation processes of photoexcited solids: A short review

Ono

2019

Trans. Mat. Res. Soc. Japan

View full text Add to dashboard Cite

Ultrafast electron dynamics of solids after an absorption of femtosecond laser pulse is governed by electron-electron, electron-phonon, phonon-electron, and phonon-phonon collisions. It is of importance to construct a framework for interpreting experimental observations correctly. In this paper we review recent developments of modeling the relaxation dynamics of solids. We discuss the ultrafast relaxation in respect to the effective temperature dynamics and the excess energy dynamics.

show abstract

Prolonged photo-carriers generated in a massive-and-anisotropic Dirac material

Cited by 14 publications

References 44 publications

Non-equilibrium band broadening, gap renormalization and band inversion in black phosphorus

Non-equilibrium band broadening, gap renormalization and band inversion in black phosphorus

Negative Terahertz Conductivity at Vertical Carrier Injection in a Black-Arsenic-Phosphorus–Graphene Heterostructure Integrated With a Light-Emitting Diode

Modeling the nonthermal relaxation processes of photoexcited solids: A short review

Contact Info

Product

Resources

About