Premium
Silicon nanowire optical Raman line shapes at cryogenic and elevated temperatures
Author(s) -
Scheel H.,
Khachadorian S.,
Cantoro M.,
Colli A.,
Ferrari A. C.,
Thomsen C.
Publication year - 2008
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.200879554
Subject(s) - raman spectroscopy , laser , superfluid helium 4 , excitation , materials science , atmospheric temperature range , nanowire , superfluidity , silicon , anharmonicity , liquid helium , atomic physics , condensed matter physics , helium , line (geometry) , molecular physics , nanotechnology , optics , chemistry , optoelectronics , physics , thermodynamics , quantum mechanics , geometry , mathematics
We report the Raman spectra of silicon nanowires (SiNWs) in a wide temperature range, between 2 K and 850 K. At room temperature we find a strong influence on the spectrum from applied laser excitation powers. These effects can be attributed a laser heated sample, leading to an inhomogeneous temperature distribution within the laser‐spot. If the laser excitation power is small (below 100 μW) such effects are negligible, and we find a temperature dependence governed by threephonon decay processes. The results from temperature dependent measurements indicate a change of sample morphology due to heating. Raman measurements on SiNWs immersed in superfluid helium at ≈ 2 K show very strong red‐shifts, even though they still have the perfect thermal contact via the superfluid helium. Considering anharmonic effects we find massively increased Si core temperatures. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom