Probing of Carrier Recombination in n- and p-Type 6H-SiC Using Ultrafast Supercontinuum Pulses

Excess carrier dynamics in 6H-SiC substrates with n- and p-type moderate doping were detected using femtosecond pump-probe measurements with supercontinuum probing. Band-to-band recombination and carrier trapping were determined as the main recombination processes in both materials. Spectral fingerprints corresponding to each of these recombination components were obtained using the global and target analysis. It was shown that, in spite of background doping, the band-to-band recombination in 6H-SiC is dominated by the excess electron absorption component and the carrier trapping is dominated by the excess hole absorption.

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Giant Photoluminescence Enhancement and Carrier Dynamics in MoS2 Bilayers with Anomalous Interlayer Coupling

Nanomaterials ◽

10.3390/nano11081994 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1994

Author(s):

Han Li ◽

Yating Ma ◽

Zhongjie Xu ◽

Xiang’ai Cheng ◽

Tian Jiang

Keyword(s):

Optical Properties ◽

Transition Metal Dichalcogenides ◽

Interlayer Coupling ◽

Carrier Dynamics ◽

Probe Signal ◽

Exciton Resonance ◽

Pump Probe ◽

Metal Dichalcogenides ◽

Photoluminescence Enhancement ◽

Probe Measurements

Fundamental researches and explorations based on transition metal dichalcogenides (TMDCs) mainly focus on their monolayer counterparts, where optical densities are limited owing to the atomic monolayer thickness. Photoluminescence (PL) yield in bilayer TMDCs is much suppressed owing to indirect-bandgap properties. Here, optical properties are explored in artificially twisted bilayers of molybdenum disulfide (MoS2). Anomalous interlayer coupling and resultant giant PL enhancement are firstly observed in MoS2 bilayers, related to the suspension of the top layer material and independent of twisted angle. Moreover, carrier dynamics in MoS2 bilayers with anomalous interlayer coupling are revealed with pump-probe measurements, and the secondary rising behavior in pump-probe signal of B-exciton resonance, originating from valley depolarization of A-exciton, is firstly reported and discussed in this work. These results lay the groundwork for future advancement and applications beyond TMDCs monolayers.

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Mid-Infrared Pump-Probe Measurements of Carrier Dynamics in Black Phosphorus

Frontiers in Optics 2017 ◽

10.1364/fio.2017.jtu3a.31 ◽

2017 ◽

Author(s):

Yigit Aytac ◽

Martin Mittendorff ◽

Thomas E. Murphy

Keyword(s):

Carrier Dynamics ◽

Black Phosphorus ◽

Pump Probe ◽

Mid Infrared ◽

Probe Measurements

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Carrier recombination processes in Fe-doped GaN studied by optical pump–probe techniques

Journal of Applied Physics ◽

10.1063/5.0009258 ◽

2020 ◽

Vol 127 (24) ◽

pp. 245705

Author(s):

Patrik Ščajev ◽

Kęstutis Jarašiūnas ◽

Jacob Leach

Keyword(s):

Optical Pump ◽

Pump Probe ◽

Carrier Recombination ◽

Recombination Processes

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Optical Characterization of Compensating Defects in Cubic SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.740-742.401 ◽

2013 ◽

Vol 740-742 ◽

pp. 401-404

Author(s):

Patrik Ščajev ◽

K. Jarašiūnas ◽

P.L. Abramov ◽

S.P. Lebedev ◽

A.A. Lebedev

Keyword(s):

Carrier Density ◽

Nonlinear Optical ◽

Carrier Lifetime ◽

Optical Trap ◽

Optical Characterization ◽

Carrier Dynamics ◽

Time Resolved ◽

Carrier Recombination ◽

P Type

We present investigation of carrier recombination and optical trap recharge in sublimation grown n- and p-type 3C layers by using time-resolved nonlinear optical techniques. Carrier lifetime and recharged trap recovery were measured by differential transmittivity technique. By monitoring nonequilibrium carrier dynamics, we analyzed impact of carrier density and temperature on carrier lifetime and recharged trap recovery rate. Large carrier lifetime and small diffusivity at low injections in highly compensated samples and their dependences on injection were explained by optical recharge of compensating aluminum impurities. The complete recharge of the compensating impurities by optical means allowed us to calculate the compensating aluminum density in n-type samples and compensating nitrogen in p-type ones.

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Carrier recombination processes in In-polar and N-polar p-type InN films

physica status solidi (b) ◽

10.1002/pssb.201100496 ◽

2012 ◽

Vol 249 (3) ◽

pp. 472-475 ◽

Cited By ~ 3

Author(s):

Daichi Imai ◽

Yoshihiro Ishitani ◽

Masayuki Fujiwara ◽

Xinqian Wang ◽

Kazuhide Kusakabe ◽

...

Keyword(s):

Carrier Recombination ◽

Recombination Processes ◽

P Type

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Dual-wavelength pump-probe measurements on helium-plasma-grown InGaAsP reveal complex carrier dynamics

Technical Digest. Summaries of papers presented at the Conference on Lasers and Electro-Optics. Postconference Edition. CLEO '99. Conference on Lasers and Electro-Optics (IEEE Cat. No.99CH37013) ◽

10.1109/cleo.1999.834248 ◽

2003 ◽

Author(s):

Li Qian ◽

S.D. Benjamin ◽

P.W.E. Smith ◽

B.J. Robinson ◽

D.A. Thompson

Keyword(s):

Carrier Dynamics ◽

Dual Wavelength ◽

Helium Plasma ◽

Pump Probe ◽

Probe Measurements

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Pump-Probe Measurements Using Silicon Nanocrystal Waveguides

MRS Proceedings ◽

10.1557/proc-770-i3.2 ◽

2003 ◽

Vol 770 ◽

Cited By ~ 1

Author(s):

Nathanael Smith ◽

Max J. Lederer ◽

Marek Samoc ◽

Barry Luther-Davies ◽

Robert G. Elliman

Keyword(s):

Probe Beam ◽

Time Resolution ◽

Pump Beam ◽

Silicon Nanocrystals ◽

Continuous Wave ◽

Optical Gain ◽

Optical Pump ◽

Time Resolved ◽

Pump Probe ◽

Probe Measurements

AbstractOptical pump-probe measurements were performed on planar slab waveguides containing silicon nanocrystals in an attempt to measure optical gain from photo-excited silicon nanocrystals. Two experiments were performed, one with a continuous-wave probe beam and a pulsed pump beam, giving a time resolution of approximately 25 ns, and the other with a pulsed pump and probe beam, giving a time resolution of approximately 10 ps. In both cases the intensity of the probe beam was found to be attenuated by the pump beam, with the attenuation increasing monotonically with increasing pump power. Time-resolved measurements using the first experimental arrangement showed that the probe signal recovered its initial intensity on a time scale of 45-70 μs, a value comparable to the exciton lifetime in Si nanocrystals. These data are shown to be consistent with an induced absorption process such as confined carrier absorption. No evidence for optical gain was observed.

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Coherent coupling effects in pump–probe measurements with collinear, copropagating beams

Optics Letters ◽

10.1364/ol.9.000359 ◽

1984 ◽

Vol 9 (8) ◽

pp. 359 ◽

Cited By ~ 44

Author(s):

T. F. Heinz ◽

K. B. Eisenthal ◽

S. L. Palfrey

Keyword(s):

Coupling Effects ◽

Pump Probe ◽

Coherent Coupling ◽

Probe Measurements

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Light Effects on Grain Boundary Properties in Silicon

MRS Proceedings ◽

10.1557/proc-5-105 ◽

1981 ◽

Vol 5 ◽

Author(s):

L. J. Cheng ◽

C. M. Shyu

Keyword(s):

Experimental Data ◽

Grain Boundary ◽

Minority Carrier ◽

State Density ◽

Boundary State ◽

Carrier Recombination ◽

Boundary Properties ◽

Light Effects ◽

Recombination Velocity ◽

P Type

ABSTRACTWe have studied the photoconductivity of grain boundaries in p–type silicon. The result demonstrates the applicability of the technique for the measurement of minority carrier recombination velocity at the grain boundary. The experimental data are consistent with the thought that the recombination velocity increases with the boundary state density and light intensity.

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