Martin Wood Complex, University of Oxford

Inspired by nature, building on spin - Christiane Timmel

• hypothesis: magnetosensitive radical pairs are formed in light sensitive proteins, aka cryptochromes
• controlling spin in molecular wires
  • controlling and quantifying spin localisation and delocalisation by design, synthesis and EPR
  • can change geometry of system as well
  • quantum interference in molecular rings
• Oxford is world leading in the understanding of cryptochromes and their importance in bird migration.

Aleks Kissinger - Quantum computing meets computer science

• ZX-calculus and quantum circuit optimisation.

Dominic O’Brien - Engineering quantum technologies

• short range indoor links: polarisation based quantum schemes
  • symmetric encryption key
• Challenges of quantum key distribution in free space:
  • daylight swamps the signal
  • people can do it between satellites, but the key rates are really slow
• Hardware: MEMS mirror based beam streaming
• Entanglement QKDs: David Lucas, Ion traps
• Dynamic optics and photonics groups
  • use lasers for fabrication inside transparent materials
  • write single NV centres in diamond

Peter Leek - superconducting quantum technology

• how do we build a quantum computer out of electric circuits
  • LC resonators, superconductors, good microwave engineering
• get very close to the ground state - remove thermal excitations (10mK)
• by using josephson junctions we can create a effective non-linear resonator which creates unequally spaced levels
• Scaling challenge: we can get to a certain scale (1000) in a fridge, then you need microwave to microwave optical conversion between fridges.

David Lucas - Ion trap technologies

• atom ion in a trap is a mass on spring, in megahertz regime.
• DIQKD challenge, need high number of Bell pairs and high fidelity.

Quantum Matter - Experimental Frontiers - Seamus Davis

• Bosons: swap you don’t change the sign by minus 1
• Fermions: you do change the sign
• Refrigerate bosons —> collapse into a single quantum state —> bose-einstein quantum state
• Refrigerate fermions —> they pair up --> superconductivity
• Correlated electron metal - Consider the Coulomb interaction within the metals and you find that the structure changes (MOTT) / HUND correlated metals