  Raman micro-spectroscopy is well suited for studying a variety of properties
and has been applied to wide- ranging areas. Combined with tuneable
temperature, Raman spectra can offer even more insights into the properties of
materials. However, previous designs of variable temperature Raman microscopes
have made it extremely challenging to measure samples with low signal levels
due to thermal and positional instability as well as low collection
efficiencies. Thus, contemporary Raman microscope has found limited
applicability to probing the subtle physics involved in phase transitions and
hysteresis. This paper describes a new design of a closed-cycle, Raman
microscope with full polarization rotation. High collection efficiency, thermal
and mechanical stability are ensured by both deliberate optical, cryogenic, and
mechanical design. Measurements on two samples, Bi2Se3 and V2O3, which are
known as challenging due to low thermal conductivities, low signal levels
and/or hysteretic effects, are measured with previously undemonstrated
temperature resolution.

Materials Science;Instrumentation and Detectors