Introduction About Quantum phase battery

Batteries belong to everyday life. A classical battery, the Volta's pile, converts chemical energy into a voltage, which can power electronic circuits. In many quantum technologies, circuits or devices are based on superconducting materials. 
In such materials, currents may flow without the need for an applied voltage; therefore, there is no need for a classical battery in such a system. 
These currents are called supercurrents because they do not exhibit any energy losses. They are induced not from a voltage but from a phase difference of the wave function of the quantum circuit, which is directly related to the wave nature of matter. A quantum device able to provide a persistent phase difference can be seen as a quantum phase battery, which induces supercurrents in a quantum circuit.

Research 

The idea was first conceived in 2015, by Sebastian Bergeret from the Mesoscopic physics group at the Materials Physics Center (CFM, CSIC-UPV/EHU), a joint initiative of Consejo Superior de Investigaciones Científicas (CSIC) and the University of the Basque Country (UPV/EHU), and Ilya Tokatly, Ikerbasque Professor in the Nano-Biospectroscopy group of the UPV/EHU, both Donostia International Physics Center (DIPC) associate researchers. They proposed a theoretical system with the properties needed to build the phase battery. It consists of a combination of superconducting and magnetic materials with an intrinsic relativistic effect, called spin-orbit coupling.

A few years later Francesco Giazotto and Elia Strambini from the NEST-CNR Institute, Pisa, identified a suitable material combination and fabricated the first quantum phase battery, the results of which are now published in the journal Nature Nanotechnology. It consists of an n-doped InAs nanowire forming the core of the battery (the pile) and Al superconducting leads as poles. The battery is charged by applying an external magnetic field, which then can be switched off.

Cristina Sanz-Fernández and Claudio Guarcello also from CFM adapted the theory to simulate the experimental findings.

The future of this battery is further being improved at CFM in a collaboration between the Nanophysics Lab and the Mesoscopic Physics Group. This work contributes to the enormous advances being made in quantum technology that are expected to revolutionize both computing and sensing techniques, as well as medicine, and telecommunications shortly.

Quantum vs “Classic” Batteries



Today, batteries are omnipresent, with lithium-ion batteries being the most common them, although alternatives do exist. These batteries convert chemical energy into a voltage that can provide power to an electronic circuit. 

In contrast, quantum technologies emphasize circuits based on superconducting materials through which a current can flow without voltage, negating the need for “classic” chemical batteries. In quantum technologies, the current is induced from a phase difference of the wave function of the quantum circuit related to the wave nature of matter.

A quantum device that can provide a continuous phase difference can be used as a quantum phase battery and induce supercurrents in a quantum circuit, powering it. 


Future references 


Quantum batteries are ever to be realized, they could bring significant benefits over their chemical cousins. Among other things, quantum batteries could offer vastly better thermodynamic efficiency and ultra-fast charging times, making them perfect for next-gen applications like electric vehicles.