We use dynamic circuits to teleport CNOT gates across 100 qubits and prepare GHZ states.
Experimental investigation of the interplay of dualities, generalized symmetries, and topological defects is an important challenge in condensed matter physics and quantum materials. A simple model exhibiting this physics is the transverse-field Ising model, which can host a noninvertible topological defect that performs the Kramers-Wannier duality transformation. When acting on one point in space, this duality defect imposes the duality twisted boundary condition and binds a single Majorana zero mode. This Majorana zero mode is unusual as it lacks localized partners and has an infinite lifetime, even in finite systems. Using Floquet driving of a closed Ising chain with a duality defect, we generate this Majorana zero mode in a digital quantum computer. We detect the mode by measuring its associated persistent autocorrelation function using an efficient sampling protocol and a compound strategy for error mitigation. We also show that the Majorana zero mode resides at the domain wall between two regions related by a Kramers-Wannier duality. Finally, we highlight the robustness of the isolated Majorana zero mode to integrability and symmetry-breaking perturbations. Our findings offer an experimental approach to investigating exotic topological defects in Floquet systems
Interacting many-body quantum systems and their dynamics, while fundamental to modern science and technology, are formidable to simulate and understand. However, by discovering their symmetries, conservation laws, and integrability one can unravel their intricacies. Here, using up to 124 qubits of a fully programmable quantum computer, we uncover local conservation laws and integrability in one- and two-dimensional periodically-driven spin lattices in a regime previously inaccessible to such detailed analysis. We focus on the paradigmatic example of disorder-induced ergodicity breaking, where we first benchmark the system crossover into a localized regime through anomalies in the one-particle-density-matrix spectrum and other hallmark signatures. We then demonstrate that this regime stems from hidden local integrals of motion by faithfully reconstructing their quantum operators, thus providing a detailed portrait of the system's integrable dynamics. Our results demonstrate a versatile strategy for extracting hidden dynamical structure from noisy experiments on large-scale quantum computers.
Digital zero-noise extrapolation (dZNE) has emerged as a common approach for quantum error mitigation (QEM) due to its conceptual simplicity, accessibility, and resource efficiency. In practice, however, properly applying dZNE to extend the computational reach of noisy quantum processors is rife with subtleties. Here, based on literature review and original experiments on noisy simulators and real quantum hardware, we define best practices for QEM with dZNE for each step of the workflow, including noise amplification, execution on the quantum device, extrapolation to the zero-noise limit, and composition with other QEM methods. We anticipate that this effort to establish best practices for dZNE will be extended to other QEM methods, leading to more reproducible and rigorous calculations on noisy quantum hardware.
Direct experimental detection of anyonic exchange statistics in fractional quantum Hall systems by braiding the excitations and measuring the wave-function phase is an enormous challenge. Here, we use a small, noisy quantum computer to emulate direct braiding within the framework of a simplified model applicable to a thin cylinder geometry and measure the topological phase. Our algorithm first prepares the ground state with two quasiholes. It then applies a unitary operation controlled by an ancilla, corresponding to a sequence of adiabatic evolutions that takes one quasihole around the other. We finally extract the phase of the wave function from measuring the ancilla with a compound error mitigation strategy. Our results open a new avenue for studying braiding statistics in fractional Hall states.
Performing quantum logic gates on multiple quantum information bits (qubits) represented by photons is challenging. Here, we invent a resource-efficient way to deterministically perform a gate that underlies the quantum Fourier transform, one of the most versatile quantum algorithms.
Science students are taught that science is a collection of facts and equations when in fact, science is a journey full of false starts, dead ends, and creative detours undertaken by scientists to uncover the truth of reality. A science student seeking to become a scientist must often regress back to a state of childlike wonder and curiosity to prepare for such a journey. We seek to spark this change with hundreds of Quick Takes and Inquiries into specifically chemistry and physics at the introductory level.
While the established infrastructure of academia promotes ventures into unknown intellectual territory, translating technologies from the enclaves of esoteric journals to the lives of everyone remains a challenge. Patents play a crucial role in the world beyond the university setting by disseminating academic work to those who can use it while financially protecting them. Here, we discuss why an academic scientist would or would not patent, review the basics of patents relevant to a university setting, walk through the steps of filing patents at a university, and provide a more holistic analysis of the role of patents in various industries.
Extracellular matrix, or what's leftover after all the cells from tissues and organs are stripped away, has been shown to promote tissue regeneration. Here, we study extracellular matrix from different tissue types, ranging from intestinal to liver to brain, and show that some stimulate tissue regenerative pathways, while others stimulate inflammatory pathways that are known to hinder tissue regeneration.