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Using time-domain terahertz spectroscopy in pulsed magnetic fields up to 31 T, we measure the terahertz optical conductivity in an optimally doped thin film of the high-temperature superconducting cuprate La1.84Sr0.16CuO4. We observe systematic changes in the circularly polarized complex optical conductivity that are consistent with cyclotron absorption of 𝑝-type charge carriers characterized by a cyclotron mass of 4.9𝑚e±0.8𝑚e and a scattering rate that increases with magnetic field. These results open the door to studies aimed at characterizing the degree to which electron-electron interactions influence carrier masses in cuprate superconductors.
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Anomalous nonlinear terahertz transmission of photoexcited carbon nanotubes
We demonstrate that free-standing multi-walled carbon nanotubes exhibit extraordinary nonlinear terahertz responses upon optical excitation. Terahertz transmission of the photoexcited nanotubes rises in a narrow range of intermediate intensity with increasing intensity, while falling in the regime of low and high intensities. A theoretical analysis shows that the nanotube conductivity drops sharply in the region of intermediate intensity and soars elsewhere. Field-effect mobility and field-induced carrier multiplications are considered to be competing processes governing the rise and fall of the conductivity.
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- Award ID(s):
- 1905634
- PAR ID:
- 10307566
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 38
- Issue:
- 10
- ISSN:
- 0740-3224; JOBPDE
- Format(s):
- Medium: X Size: Article No. 3130
- Size(s):
- Article No. 3130
- Sponsoring Org:
- National Science Foundation
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