Electrical and Electronics Metrology: From Quantum Standard to Applications in Industry and Strategic Sectors

Abstract

CSIR-NPL is the custodian of National standards of electrical and electronic parameters. These include DC parameters such as voltage, current and resistance; low frequency and high frequency impedance related quantities such as capacitance, inductance and AC resistance; AC/DC high voltage and AC high current; AC power and energy; and quantum standard which includes quantum hall resistance (QHR), quantum current (QC) and quantum nanophotonics (QN). The metrological traceability of the electrical and electronics parameters to SI units is derived from Josephson Voltage Standard (JVS), Quantum Hall Resistance (QHR) standard and frequency (time) standards; all of them are being maintained at CSIR-NPL with metrological precision at par with international standards. The traceability of the aforementioned parameters is disseminated through an unbroken chain of apex level calibrations and testing at par with international level to the industries and strategic sectors of the country to improve the quality of life, which in turn will lead to the inclusive growth of the country and economic development. R&D efforts on the development of quantum standards is a constant endeavour and continues to be at the forefront. Specifically, CSIR-NPL focuses on the development of quantum standards related to the unit of current (ampere), the unit of resistance (ohm) and quantum nanophotonics which aims for detection of few photons (or even single photons) using the novel concept of superconducting nanowire single photon detectors (SNSPD). Among these the research on QC needs special mention, as this will lead to realisation of the SI unit of electric current (ampere), the only unit out of the seven base units of SI system. The quantum current standard (QCS) realisation is bifurcated into two approaches, (i) based on the single electron tunnelling effect (SET) observable in semiconductor quantum dot (QD) structures and (ii) the quantum phase slip phenomenon (QPS) observable in superconducting nanowires of cross-sectional area of the order of coherence length of the system. The realisation of the resistance unit (ohm) is based on the quantum hall effect observable in semiconductor 2DEG structures such as GaAs/AlGaAs systems. Recently there has been tremendous evidence emerging for the use ofmonolayer graphene for the use of QHR metrology. CSIR-NPL also started the growth of “epitaxial graphene anchored on SiC” and have obtained encouraging results. The nano-photonics measurement research is also taken up actively for its applications to realize quantum standards for optical radiation and device fabrication.