Radiation detector

A method for detecting radiation by a radiation detector, the radiation detector comprising a waveguide structure and a sensing structure comprising a phase change material, the phase change material having a first phase state at a first temperature range and a second phase state at a second temperature range, the sensing structure being arranged in an evanescent field area of the waveguide structure;

• the method comprising:
• transmitting, by an optical transmitter, an optical sensing signal via the waveguide structure to an optical receiver;
• providing, by the phase change material, to the evanescent field of the optical sensing signal a first complex refractive index in the first phase state and a second complex refractive index in the second phase state, the first complex refractive index being different from the second complex refractive index;
• receiving, by the optical receiver, the optical sensing signal from the transmitter;
• measuring a transmission of the waveguide structure for the sensing signal;
• and
• deriving the phase state of the phase change material in dependence on the transmission of the waveguide structure for the sensing signal.

A computer program product for operating a radiation detector having a waveguide structure, a sensing structure comprising a phase change material, an optical transmitter and optical receiver, said computer program product comprising a non-transitory computer readable storage medium having program instructions embodied therewith, the program instructions executable by the radiation detector to perform a method comprising:

• transmitting, by the optical transmitter, an optical sensing signal via the waveguide structure to the optical receiver;
• providing, by the phase change material, to the evanescent field of the optical sensing signal a first complex refractive index in the first phase state and a second complex refractive index in the second phase state, the first complex refractive index being different from the second complex refractive index;
• receiving, by the optical receiver, the optical sensing signal from the transmitter;
• measuring a transmission of the waveguide structure for the sensing signal;
• and
• deriving the phase state of the phase change material in dependence on the transmission of the waveguide structure for the sensing signal.