New concept of using interferometer sensors in security systems

New concept of using interferometer sensors in security systems
M. Szustakowski, M. Zyczkowski, M. Karol*, L. Olszewski
Institute of Optoelectronics, Military University of Technology, Poland
*mateusz.karol@wat.edu.pl

Current state in research of quantum technology usage are mainly focused on developing quantum computers and quantum cryptography. Transmission of information with use of this technology requires transmission of single photons over long distances using a fiber optic medium. These medium may introduce transmission disturbances such as changes in polarization and phase. Another problem encountered with single-photon transmission is the generation and detection of single photons.
The article explains how influence compensation in single-photon transmission system is obtained for changes in polarization and phase generated by external disturbances acting on the transmission line. For the study on the implemented solutions effectiveness transmission line simulator has been made. Simulation system using a Mach-Zehnder interferometer to determine the parameters of the actual communication link was build. The study was based on single-photon transmission system in order to verify the operation of the simulator developed. studies were conducted on the impact of mechanical disorders of transmission speed and error rate in single-photon transmission channel.
This paper presents a different approach to the subject of quantum systems use in the information protection. Test results of fiber optic sensor systems tests are presented and analysed for use in protection systems
The first of the systems described is one fiber pulse Mach-Zehnder interferometer structure allowing for the automatic compensation of environmental changes introduced into the system, regardless of distance. Disorders of the sensor lines are observed as detuning of the maximum value of the interference fringe. Because of pulsed character of sensor response, state observed at the output of the system is determined by using the maximum value for each interference pulse.
The second described system is quantum system. A system for detecting abnormalities in line use single photons. The construction of this circuit is similar to the pulse interferometer, but it requires the use of a suitable source and detector elements. Zero one nature of detected signal requires averaging the photons count in time. Changes in the levels of counts in time interval allow for detection of disorders line.
Presented sensor systems show a new approach to protect the fiber with a relatively simple design, however, requires the use of high-end devices. Furthermore, it is possible to integrate the sensor signal with the signal data which can provide unconditional security of the transmission.