US 12,493,316 B2
Photonic blockchain based on optical proof-of-work
Sunil K. Pai, San Jose, CA (US); David A. B. Miller, Stanford, CA (US); Olav Solgaard, Stanford, CA (US); Shanhui Fan, Stanford, CA (US); Michael Dubrovsky, Somerville, MA (US); Bogdan Penkovsky, Strassbourg (FR); and Maynard Marshall Ball, Jr., New York, NY (US)
Assigned to The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US); and PoWx inc., Somerville, MA (US)
Filed by The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US); and PoWx inc., Somerville, MA (US)
Filed on Mar. 25, 2023, as Appl. No. 18/126,436.
Claims priority of provisional application 63/323,727, filed on Mar. 25, 2022.
Prior Publication US 2024/0004417 A1, Jan. 4, 2024
Int. Cl. G06E 1/04 (2006.01); G02F 3/02 (2006.01); G06Q 20/38 (2012.01)
CPC G06E 1/045 (2013.01) [G02F 3/02 (2013.01); G06Q 20/3827 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An apparatus for combined digital and optical processing of a cryptocurrency data block, the apparatus comprising:
(a) a digital processor configured to perform a first hash computation to produce a hash vector from the cryptocurrency data block;
(b) a laser and splitter configured to produce optical input signals;
(c) optical modulators configured to binary phase-shift key modulate the optical input signals based on the hash vector to produce modulated optical input signals, wherein each of the modulated optical input signals is limited to a first set of discrete values;
(d) a photonic matrix multiplier circuit configured to optically perform a discrete matrix-vector product operation on the modulated optical input signals to produce optical output signals, wherein the discrete matrix-vector product operation is defined by matrix elements, each of which is limited to a set of K discrete values, where 2≤K≤17; wherein each of the optical output signals is limited to a second set of discrete values;
(e) photodetectors and comparators configured to perform optoelectronic conversions of the optical output signals to produce corresponding digital electronic output signals;
(f) wherein the digital processor is also configured to perform a second hash computation on an XOR result between the digital electronic output signals and the hash vector to produce a proof of work result.