Time Crystals: Next Frontier For Quantum Computing & Memory
Time Crystals Open New Memory Paths. Fast-growing quantum computing requires reliable and efficient data processing and storage. Recent discoveries in time crystals, a phase of matter with constantly moving particles, promise quantum memory and secure communication.
Complex quantum hardware has been employed in many time crystal experiments, but new theoretical frameworks and classical systems are expanding understanding and opening new quantum possibilities.
Possible Quantum Computing Memory Solution: Time Crystals? Its natural stability makes it a promising memory material for quantum computers. Its pattern repeats over time, unlike ordinary crystals, which contain atoms scattered in space. Their “motion without energy” in a fixed pattern over time, where entropy maintains constant, makes them desirable for dependable information storage. Engineers seek to harness time crystals to construct cutting-edge devices.
Early Quantum Implementations and Milestones
Quantum computing has had a major impact on time crystal lab development.
Norman Yao and colleagues at Berkeley presented a discrete time crystal method for spin systems in 2016. Two experimental teams separately realized these concepts in March 2017: Christopher Monroe's University of Maryland group detected discrete time-crystalline order in trapped-ion chains, while Mikhail Lukin's Harvard group observed it in a disordered dipolar many-body system. Monroe and colleagues trapped a chain of 171Yb+ ions and observed a subharmonic driving oscillation to establish the time crystal's “rigidity”. Lukin's team witnessed spin polarisation evolve over 100 cycles at half the microwave drive's frequency in a diamond crystal with nitrogen-vacancy centres.
Google and other university physicists discovered a discrete time crystal on their quantum computing device Sycamore processor in July 2021. A tremendous achievement. They created a many-body localization arrangement of spins and excited it with a laser using a 20-qubit processor to generate a regularly driven “Floquet” system. The spins flipped in cycles multiples of the laser's frequency without energy absorption, suggesting a protected eigenstate order.
Other teams created “virtual time crystals” using quantum simulators in June and November 2021 before Google. University of Maryland researchers drove trapped-ion qubits at high frequency. A cooperation between TU Delft and TNO (Qutech) developed longer durations but fewer qubits from nuclear spins in carbon-13 nitrogen-vacancy (NV) centres on a diamond.
In March 2022, two University of Melbourne researchers tested IBM's Manhattan and Brooklyn quantum processors and found time crystal behavior in 57 qubits.
Robustness and Error Correction in Quantum Systems
Self-healing and disturbance resilience are its most essential traits. In a few cycles, fresh liquid crystal time crystals can restore to their ordered pattern after a fault. Stability is crucial for quantum error correction since qubits are notoriously brittle. Despite being classical systems, liquid crystal time crystals' tolerance to disturbance may help us build robust quantum computer architectures.
Quantum Technologies using Classical Time Crystals
The recent construction of visible time crystals using liquid crystals by CU Boulder physicists Hanqing Zhao and Ivan Smalyukh shows that time crystallinity is not limited to quantum physics. Despite operating at lower frequencies and not being suitable for direct quantum hardware without considerable scaling, they are regarded a “bridge between classical and quantum”. Easy-to-use platforms can support theoretical frameworks and inspire new classical and quantum concepts for studying temporal symmetry breaking.
These liquid crystal time crystals and polarized light may provide dynamic optical components for quantum communication photonic technologies. Since they can manage optical signal temporal modulation, these devices could improve data encoding or test quantum-inspired protocols.
Future Challenges and Directions
Time crystals have great potential for quantum computing, but they face challenges. Existing time crystals must have their temporal frequencies boosted and spatial periodicity reduced down to fit visible or telecom light wavelengths for direct incorporation into quantum technologies. Ongoing research, including the discovery of intricate nonlinear behavior in semiconductor-based time crystals and ones with remarkable durations, shows how quickly we are learning to create these special materials for a future that may depend more on quantum technologies.