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

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

Materials Science Forum ◽

10.4028/www.scientific.net/msf.821-823.245 ◽

2015 ◽

Vol 821-823 ◽

pp. 245-248 ◽

Cited By ~ 1

Author(s):

Paulius Grivickas ◽

Stephen Sampayan ◽

Kipras Redeckas ◽

Mikas Vengris ◽

Vytautas Grivickas

Keyword(s):

Carrier Dynamics ◽

Pump Probe ◽

Absorption Component ◽

Carrier Trapping ◽

Carrier Recombination ◽

Recombination Processes ◽

Background Doping ◽

P Type ◽

Excess Hole ◽

Probe Measurements

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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Indium selenide film: a promising saturable absorber in 3- to 4-μm band for mid-infrared pulsed laser

Nanophotonics ◽

10.1515/nanoph-2020-0068 ◽

2020 ◽

Vol 9 (7) ◽

pp. 2045-2052 ◽

Cited By ~ 3

Author(s):

Ting Hai ◽

Guoqiang Xie ◽

Zhen Qiao ◽

Zhipeng Qin ◽

Jie Ma ◽

...

Keyword(s):

Saturable Absorber ◽

Pulsed Laser ◽

Indium Selenide ◽

Saturable Absorption ◽

Nonlinear Characteristics ◽

Pump Probe ◽

Mid Infrared ◽

Inse Film ◽

Probe Measurements ◽

Absorption Measurements

AbstractIndium selenide (InSe) film, an emerging two-dimensional chalcogenide semiconductor, has recently attracted growing interests in optoelectronics. However, its nonlinear characteristics and application potentials in mid-infrared (IR) region remain open, which is a very attractive but undeveloped spectral region currently. In this work, it is demonstrated that InSe film possesses excellent nonlinear absorption properties in 3- to 4-μm band. Saturable absorption measurements of InSe film at 2.8 and 3.5 μm show very low saturation energy fluences and moderate modulation depths. Pump–probe measurements at 3 and 4 μm indicate that InSe film has ultrafast responses in mid-IR region. Furthermore, the application of InSe film in mid-IR pulsed laser is demonstrated, and stable Q-switching operation of fiber laser at 2.8 μm is realized. These results show that InSe film is a promising saturable absorber for mid-IR pulsed laser.

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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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Mid-infrared ultrafast carrier dynamics in thin film black phosphorus

2D Materials ◽

10.1088/2053-1583/aa74ab ◽

2017 ◽

Vol 4 (2) ◽

pp. 021032 ◽

Cited By ~ 19

Author(s):

Vasudevan Iyer ◽

Peide Ye ◽

Xianfan Xu

Keyword(s):

Thin Film ◽

Carrier Dynamics ◽

Black Phosphorus ◽

Mid Infrared ◽

Ultrafast Carrier Dynamics ◽

Ultrafast Carrier

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Intraband dynamics of mid-infrared HgTe quantum dots

Nanoscale ◽

10.1039/d1nr07007j ◽

2021 ◽

Author(s):

Matthias Ruppert ◽

Hanh Bui ◽

Laxmi Kishore Sagar ◽

Pieter Geiregat ◽

Zeger Hens ◽

...

Keyword(s):

Quantum Dots ◽

Energy Dissipation ◽

Dissipation Rate ◽

Energy Dissipation Rate ◽

Carrier Dynamics ◽

Excitation Wavelength ◽

Pump Probe ◽

Mid Infrared ◽

Ultrafast Carrier ◽

Probe Spectroscopy

Femtosecond pump–probe spectroscopy reveals ultrafast carrier dynamics in mid-infrared (MIR) colloidal HgTe nanoparticles with a bandgap of 2.5 μm at a mean energy dissipation rate of 0.36 eV ps−1 irrespective of excitation wavelength.

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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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