TY  - JOUR
AU  - Irbäck, Anders
AU  - Knuthson, Lucas
AU  - Mohanty, Sandipan
TI  - Folding lattice proteins confined on minimal grids using a quantum-inspired encoding
JO  - Physical review / E
VL  - 112
IS  - 4
SN  - 2470-0045
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2025-04091
SP  - 045302
PY  - 2025
AB  - Steric clashes pose a challenge when exploring dense protein systems using conventional explicit-chain methods. A minimal example is a single lattice protein confined on a minimal grid, with no free sites. Finding its minimum energy is a hard optimization problem, with similarities to scheduling problems. It can be recast as a quadratic unconstrained binary optimization (QUBO) problem amenable to classical and quantum approaches. We show that this problem in its QUBO form can be swiftly and consistently solved for chain length 48, using either classical simulated annealing or hybrid quantum-classical annealing on a D-Wave system. In fact, the latter computations required about 10 s. We also test linear and quadratic programming methods, which work well for a lattice gas but struggle with chain constraints. All methods are benchmarked against exact results obtained from exhaustive structure enumeration, at a high computational cost.
LB  - PUB:(DE-HGF)16
DO  - DOI:10.1103/8n7p-7lh2
UR  - https://juser.fz-juelich.de/record/1047045
ER  -