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Title: Scaling Phononic Quantum Networks of Solid-State Spins with Closed Mechanical Subsystems
Phononic quantum networks feature distinct advantages over photonic networks for on-chip quantum communications, providing a promising platform for developing quantum computers with robust solid-state spin qubits. Large mechanical networks including one-dimensional chains of trapped ions, however, have inherent and well-known scaling problems. In addition, chiral phononic processes, which are necessary for conventional phononic quantum networks, are difficult to implement in a solid-state system. To overcome these seemingly unsolvable obstacles, we have developed a new network architecture that breaks a large mechanical network into small and closed mechanical subsystems. This architecture is implemented in a diamond phononic nanostructure featuring alternating phononic crystal waveguides with specially-designed bandgaps. The implementation also includes nanomechanical resonators coupled to color centers through phonon-assisted transitions as well as quantum state transfer protocols that can be robust against the thermal environment.  more » « less
Award ID(s):
1641084
NSF-PAR ID:
10099952
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Physical review. X
Volume:
8
ISSN:
2160-3308
Page Range / eLocation ID:
041027
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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