The focus of quantum sensing is to harness the high sensitivity of coherent quantum systems to external perturbations to enhance the performance and precission of measurementsof physical quantities. Exploiting the quantum properties of entanglement and coherence, quantities such as mass, charge, magnetic and electric fields, and temperature can be measured with a sensitivity which significantly exceeds any classical methodologies. One of the most promising platforms to implement the ideas of quatum sensing are nitrogen vacancy centers in diamonds, whose long coherence times and high sensitivity to magnetic fields mean that their capacity to detect and measure frequencies is unparalleled. In this direction, we focus on developing new algorithms and measurement techniques that aid in the experimental research and technological deployment of new devices with increased precision.
- Amit Rotem, Tuvia Gefen, Santiago Oviedo-Casado, Javier Prior, Simon Schmitt, Yoram Burak, Liam McGuiness, Fedor Jelezko, and Alex Retzker, Limits on spectral resolution measurements by quantum probes, Phys. Rev. Lett. 122, 060503 (2019).
Quantum effects in biology
Quantum biology has developed over the past decade as a result of convergence between quantum mechanics and biology. This field stems from the interrogation of the basic principles that govern interactions at the molecular scale in living organisms. Traditionally, the principles of quantum mechanics have been used to explain a wide range of observed phenomena in physics and chemistry. Experiments that have provided evidence of quantum mechanical behaviour have, in most cases, been performed in highly controlled environments using tools that allow the measurement and manipulation of nanoscale objects such as atoms, single molecules, or ordered solid-state systems. Biological phenomena involve molecules (such as proteins) that are composed of typically hundreds of thousands of atoms and have, therefore, been considered too complex to be tackled by physicists using similar quantum mechanical approaches. However, recent evidence of quantum phenomena occurring in living organisms suggests that quantum mechanics does play a role in biological systems:
- Alex Chin, Javier Prior, R. Rosenbach, F. Caycedo-Soler, S.F. Huelga and M.B. Plenio. The Role of non-equilibrium vibrational structures in electronic coherence and recoherence in pigment-protein complexes, Nature Phys. 9, 113-118 (2013).
The development of classical thermodynamics in the 19th century underpinned the Industrial Revolution, and the enormous economic growth and social changes that followed. Now, in the 21st century, the burgeoning quantum technological revolution promises unprecedented advances in our computation and communication capabilities, enabled by harnessing quantum coherence. As our machines are scaled down into the quantum regime, it is of prime importance to understand how quantum mechanics affects the operation of these devices. This problem has attracted great interest to the field of quantum thermodynamics over the last few years.
- MT Mitchison, MP Woods, J Prior, M Huber, Coherence-assisted single-shot cooling by quantum absorption refrigerators, New Journal of Physics, 17, 115013 (2015).
Quantum Many-Body Systems
Quantum many-body systems appear very naturally in several fields of Physics, like Condensed Matter, High Energy Physics, quantum information or quantum biology. During the last years we have been working in the development of theoretical tools in order to describe many-body quantum systems. The main problem in describing the states of a set of particles is that the number of parameters increases exponentially with the number of particles and then it is important to identify subsets in state space that are well suited to describe a certain system and allow for an efficient description. One may try to devise new ways of representing many-particle states so that physical quantities can be efficiently calculated. In this direction the study of entanglement in many-body systems has led to a deeper understanding of quantum phase transitions and the performance of numerical algorithms such as the density matrix renormalization group (DMRG) with allows to reduce the exponential grows of the complexity of the quantum system . Understanding the structure of state space and particular states such as ground and thermal states is one of the major topics in the quantum information theoretical assessment of many-body systems.
- Javier Prior, Alex Chin, Susana F. Huelga and Martin B. Plenio. Efficient Simulation of Strong System-Environment Interactions, Phys. Rev. Lett. 105, 050404 (2010).