Optical-field induced SU(2) pair potential in caesium lead halide perovskites

Motivated by the controversial bright exciton splittings in inorganic cesium lead halide perovskite nanocrystals, we studied excitation state of perovskite CsPbBr3 by four-band model Hamiltonian. With spin–orbit coupling, the calculated band structure shows that the double degeneracy of each band around [Formula: see text] point is removed because of broken spatial inversion symmetry (SIS). With broken SIS, ring-shaped valence band maximum is formed in the band structure of ground state, and SU(2) vector potential in momentum is created with the excitation of one electron from valence band to conduction band by photon absorption. In the case of low density carrier, our theory also predicts that the energy splitting between the four binding electron-hole states by the vector potential is proportional to the power of laser light which certainly stimulates further experimental work in this intriguing topic.

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Investigation of the valence band structure of PbSe by optical and transport measurement

MRS Proceedings ◽

10.1557/opl.2013.150 ◽

2013 ◽

Vol 1490 ◽

pp. 75-81 ◽

Cited By ~ 2

Author(s):

Thomas C. Chasapis ◽

Yeseul Lee ◽

Georgios S. Polymeris ◽

Eleni C. Stefanaki ◽

Euripides Hatzikraniotis ◽

...

Keyword(s):

Band Structure ◽

Valence Band ◽

Room Temperature ◽

Heavy Hole ◽

Light Hole ◽

Band Model ◽

Valence Band Structure ◽

Effective Masses ◽

Wide Range ◽

Two Band Model

ABSTRACTWe investigated the valence band structure of PbSe by a combined study of the optical and transport properties of p-type Pb1-xNaxSe, with Na concentrations ranging from 0 – 4%, yielding carrier densities in a wide range of 1018 – 1020 cm−3. Room temperature infrared reflectivity studies showed that the susceptibility (or conductivity) effective mass m* increases from ∼ 0.06mo to ∼ 0.5mo on increasing Na content from 0.08% to 3%. The Seebeck coefficient scales with doping in the whole temperature range, yielding lower values for higher Na contents, while the Hall coefficient increases on heating from room temperature showing a peak close to 650 K. The room temperature Pisarenko plot is well described by the simple parabolic band model up to ∼ 1·1020 cm−3. In order to describe the behaviour in the whole concentration range, the application of the two band model, i.e. light hole and heavy hole, was used giving density of states effective masses 0.28mo and 2.5mo for the two bands respectively.

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Photocurrent spectroscopy of single CdS nanosheets: Valence band structure and two photon absorption

Applied Physics Letters ◽

10.1063/1.3573859 ◽

2011 ◽

Vol 98 (14) ◽

pp. 143102 ◽

Cited By ~ 8

Author(s):

P. Kumar ◽

A. Wade ◽

L. M. Smith ◽

H. E. Jackson ◽

J. M. Yarrison-Rice ◽

...

Keyword(s):

Band Structure ◽

Valence Band ◽

Photon Absorption ◽

Valence Band Structure ◽

Two Photon Absorption ◽

Two Photon ◽

Photocurrent Spectroscopy

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PHOTOEMISSION STUDY OF PURE AND Cs-INTERCALATED VSe2

Modern Physics Letters B ◽

10.1142/s0217984994001254 ◽

1994 ◽

Vol 08 (20) ◽

pp. 1261-1268 ◽

Cited By ~ 15

Author(s):

H.I. STARNBERG ◽

H.E. BRAUER ◽

P.O. NILSSON ◽

L.J. HOLLEBOOM ◽

H.P. HUGHES

Keyword(s):

Charge Transfer ◽

Band Structure ◽

Valence Band ◽

Band Model ◽

Valence Band Structure ◽

Band Structure Calculations ◽

Band Dispersion ◽

Self Consistent ◽

Photoemission Study ◽

Structure Calculations

We report photoemission studies of the valence band structure of VSe 2 and of VSe2 intercalated with Cs. Pure VSe 2 showed significant band dispersion both perpendicular and parallel to the layers, i.e. the valence band of VSe 2 is 3D in character, confirming self-consistent LAPW band structure calculations. After Cs intercalation the perpendicular band dispersion vanished, while that parallel to the layers remained, showing that the valence band structure had become 2D. The observed changes go far beyond the rigid band model, but are largely understandable in terms of intercalation-induced decoupling of the VSe 2 layers, and charge transfer from the Cs.

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Location of the valence band maximum in the band structure of anisotropic 1T′−ReSe2

Physical Review B ◽

10.1103/physrevb.97.165130 ◽

2018 ◽

Vol 97 (16) ◽

Cited By ~ 3

Author(s):

P. Eickholt ◽

J. Noky ◽

E. F. Schwier ◽

K. Shimada ◽

K. Miyamoto ◽

...

Keyword(s):

Band Structure ◽

Valence Band ◽

Valence Band Maximum ◽

Band Maximum

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Electronic Structures of the High-Pressure hcp and bcc Phases of Al: A Computer Aided Design and Simulation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.523 ◽

2014 ◽

Vol 556-562 ◽

pp. 523-526

Author(s):

Chao Xu ◽

Dong Chen

Keyword(s):

High Pressure ◽

Band Structure ◽

Valence Band ◽

Conduction Band ◽

Electronic Structures ◽

Computer Aided Design ◽

Valence Band Maximum ◽

Lattice Constants ◽

Wave Methods ◽

Aided Design

Thestate-of-the-artplane-wave methods combined with ultra-soft pseudo-potentials were employed to study the crystal and electronic structures (density of state, band structure) of aluminum in its hcp and bcc structures. In our computation we used the PBE functional, which predicts lattice constants very close to the experimental data. The calculations reveal that the whole valence band of Al is dominated by the 3s and 3p states while the conduction band is mainly contributed by the 3p band. The band structure shows that bcc-Al has a 0eV gap, which reflects its metallic character. The dispersion curves near the valence band maximum and conduction band minimum are quite flat. Generally speaking, our work is an attempt to study the high pressure electronic structures of Al, which needs to be verified by experiments.

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