Room-temperature photonic logical qubits via second-order nonlinearities

Abstract

Recent progress in nonlinear optical materials and microresonators has brought quantum computing with bulk optical nonlinearities into the realm of possibility. This platform is of great interest, not only because photonics is an obvious choice for quantum networks, but also as a promising route to quantum information processing at room temperature. We propose an approach for reprogrammable room-temperature photonic quantum logic that significantly simplifies the realization of various quantum circuits, and in particular, of error correction. The key element is the programmable photonic multi-mode resonator that implements reprogrammable bosonic quantum logic gates, while using only the bulk χ(2) nonlinear susceptibility. We theoretically demonstrate that just two of these elements suffice for a complete, compact error-correction circuit on a bosonic code, without the need for measurement or feed-forward control. Encoding and logical operations on the code are also easily achieved with these reprogrammable quantum photonic processors. An extrapolation of current progress in nonlinear optical materials and photonic circuits indicates that such circuitry should be achievable within the next decade.

2022 Roadmap on integrated quantum photonics

“…Recent progress in nonlinear optical materials and micro-/nano-resonators has brought single-photon non-linearity employing bulk optical nonlinearities into the realm of possibility [96]. One significant advantage of this approach is its great potential for emitter-free, room temperature quantum photonics applications.…”

“…Higher-order entanglement (dimension d > 2) allows for more information (qudits) to be transported by photons, which are inevitably lost due to absorption, scattering or diffraction during propagation [95]. Since scalability of on-demand entangled-photon sources has not yet been realized, current practice relies on multiplexing probabilistic pair sources through linear optical gates and post-selection [6,34], but other schemes have been proposed [96].…”

Topological Silicon Photonics

“…[ 96–99 ] Indeed, the success of these topologies in the context of silicon photonics will hinge on configurations that likewise allow all‐dielectric configurations without the use of gyromagnetic materials or applications of magnetic fields and to a certain degree, the feasibility of operation at the telecommunications wavelength. [ 100 ]…”

New Modular Organic Platform For Understanding The Effect Of Structural Changes On Slow Magnetic Relaxation In Mononuclear Octahedral Copper(II) Complexes

“…Molecular nanomagnets (MNMs) are a research focus of scientists due to a variety of potential applications [1][2][3][4] , including molecular spintronics 1,5,6 , high-density information storage [7][8][9] , quantum information processing or sensing. [10][11][12][13][14][15][16] These systems display magnetic hysteresis below their blocking temperature (TB) and are magnetically bi-stable, exhibiting an energy barrier to spin reversal (Ueff) [17][18][19][20][21][22] , ultimately manifested by macroscopic quantum tunneling and slow relaxation of magnetization. The archetypal Single Molecule Magnet (SMM) is a dodecanuclear manganese cluster, [Mn12O12(OAc)16(H2O)4] •2MeCO2H•4H2O, magnetically characterized by R. Sessoli, D. Gatteschi et al, exhibiting Ueff = 60 K and TB=3K.…”