Noise-resilient edge modes on a chain of superconducting qubits

Abstract

Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model, which exhibits nonlocal Majorana edge modes (MEMs) with ℤ 2 parity symmetry. We find that any multiqubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment.

Simulating prethermalization using near-term quantum computers

“…Here, 𝑝 is the probability that the channel causes an error on the qubit. The state of art gate error rate is around 0.5% for two-qubit gates [13,14], motivating our choice of 𝑝 = 0.3% per qubit per gate as the reference value in our model [54].…”

“…In circuit-based quantum computers, continuoustime dynamics can be approximated using, for example, Trotterization [8]. With state-of-the-art gate errors [9][10][11][12][13][14], it is however only possible to run simulations with a controlled Trotter error up to short times, which are insufficient to explore thermalization in classically intractable systems (50 or so qubits in two or more dimensions).…”

Non-Hermitian topological quantum states in a reservoir-engineered transmon chain

“…So far, the quantum effects of the NH topology have not been extensively explored in these systems. Superconducting circuits, such as arrays of transmon devices [33], are currently used in the most sophisticated attempts to build a scalable quantum computer [34][35][36][37] and to simulate electronic properties [38] and topological phases [39,40]. However, their potential in realizing NH topological quantum phases remains to be explored.…”

Dissipation and Dephasing of Interacting Photons in Transmon Arrays

“…Transmon arrays have recently taken substantial advances in size, coherence, and controllability, opening doors for exciting demonstrations of quantum information protocols [1][2][3][4][5][6][7][8][9][10][11][12][13] and many-body simulations [14][15][16][17][18][19][20][21][22][23][24][25][26][27]. Transmons are typically operated as quantum two-level systems, qubits, despite their inherent nature as anharmonic oscillators with approximately d ∼ 5 − 10 welldefined quantum states [28].…”