Phase change in terahertz waves emitted from differently doped graphite: The role of carrier drift

Journal Article · Mon Nov 11 00:00:00 EST 2013 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4830370· OSTI ID:22254069

Irfan, Muhammad; Yim, Jong-Hyuk; Jho, Young-Dahl ^[1]; Kim, Changyoung ^[2]; Wook Lee, Sang ^[3]

---

1. School of Information and Communications, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)
2. Institute of Physics and Applied physics, Yonsei University, Seoul 120-749 (Korea, Republic of)
3. Division of Quantum Phases and Devices, School of Physics, Konkuk University, Seoul 143-701 (Korea, Republic of)

We investigate characteristics of THz waves radiated from differently doped graphite samples excited by femtosecond laser pulses. Between n-type single-crystalline graphite and p-type polycrystalline graphite films, we observe the phase reversal of THz waves regardless of excitation energy variations around K-valley. In addition, variations in other parameters such as excitation fluence and azimuthal angle produce no changes in the phase of THz waves, which correlate well with the opposite dipole polarization between differently doped samples rather than unidirectional diffusive transport.

• OSTI ID: 22254069
• Journal Information: Applied Physics Letters, Vol. 103, Issue 20; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
DOPED MATERIALS
FILMS
GRAPHITE
LASERS
MONOCRYSTALS
POLARIZATION
POLYCRYSTALS
PULSES