Qutrit Randomized Benchmarking.

Ternary quantum processors offer significant potential computational advantages over conventional qubit technologies, leveraging the encoding and processing of quantum information in qutrits (three-level systems). To evaluate and compare the performance of such emerging quantum hardware it is essential to have robust benchmarking methods suitable for a higher-dimensional Hilbert space. We demonstrate extensions of industry standard randomized benchmarking (RB) protocols, developed and used extensively for qubits, suitable for ternary quantum logic. Using a superconducting five-qutrit processor, we find an average single-qutrit process infidelity of 3.8×10^{-3}. Through interleaved RB, we characterize a few relevant gates, and employ simultaneous RB to fully characterize crosstalk errors. Finally, we apply cycle benchmarking to a two-qutrit CSUM gate and obtain a two-qutrit process fidelity of 0.85. Our results present and demonstrate RB-based tools to characterize the performance of a qutrit processor, and a general approach to diagnose control errors in future qudit hardware.

Realization of a Λ System with Metastable States of a Capacitively Shunted Fluxonium.

We realize a Λ system in a superconducting circuit, with metastable states exhibiting lifetimes up to 8 ms. We exponentially suppress the tunneling matrix elements involved in spontaneous energy relaxation by creating a "heavy" fluxonium, realized by adding a capacitive shunt to the original circuit design. The device allows for both cavity-assisted and direct fluorescent readouts, as well as state preparation schemes akin to optical pumping. Since direct transitions between the metastable states are strongly suppressed, we utilize Raman transitions for coherent manipulation of the states.

Universal Stabilization of a Parametrically Coupled Qubit.

We autonomously stabilize arbitrary states of a qubit through parametric modulation of the coupling between a fixed frequency qubit and resonator. The coupling modulation is achieved with a tunable coupling design, in which the qubit and the resonator are connected in parallel to a superconducting quantum interference device. This allows for quasistatic tuning of the qubit-cavity coupling strength from 12 MHz to more than 300 MHz. Additionally, the coupling can be dynamically modulated, allowing for single-photon exchange in 6 ns. Qubit coherence times exceeding 20 µs are maintained over the majority of the range of tuning, limited primarily by the Purcell effect. The parametric stabilization technique realized using the tunable coupler involves engineering the qubit bath through a combination of photon nonconserving sideband interactions realized by flux modulation, and direct qubit Rabi driving. We demonstrate that the qubit can be stabilized to arbitrary states on the Bloch sphere with a worst-case fidelity exceeding 80%.

Solid pseudopapillary epithelial neoplasm of pancreas in pregnancy: A case report and review of literature.

The solid pseudopapillary epithelial neoplasm (SPEN) of the pancreas is an uncommon tumor that accounts for approximately 1%-2% of exocrine pancreatic neoplasms. It predominantly affects female in their second and third decades of life. In this case report, we present a clinical scenario of a 21-year-old pregnant woman who incidentally discovered a solid cystic lesion in her pancreas, exhibiting features suggestive of SPEN. The patient underwent surgery during the second trimester. Management of pregnant females with SPEN poses challenges due to the absence of definitive treatment guidelines, particularly in determining the ideal timing for surgical intervention. Notably, during pregnancy, the presence of a small SPEN does not necessarily require immediate resection. However, if the tumor is of significant size, it can give rise to complications such as tumor rupture, multivisceral resection, recurrence, spontaneous abortion, intrauterine growth restriction, or premature delivery if not addressed. In the existing literature, a common finding is that approximately two-thirds of pregnant females with SPEN underwent surgery in the second trimester, often without complications for the mother or fetus. All these tumors were larger than 8 cm. The decision to operate before or after birth can be individualized based on team discussion. However, delay in surgery may lead to larger tumors and higher risks like bleeding, rupture, multivisceral resection, and recurrence. Therefore, second-trimester surgery seems safer, and lessens dangers, emergency surgery, and tumor recurrence.

Publisher Correction: Random access quantum information processors using multimode circuit quantum electrodynamics.

In the original version of this Article, the affiliation details for Peter Groszkowski and Jens Koch were incorrectly given as 'Department of Physics, University of Chicago, Chicago, IL, 60637, USA', instead of the correct 'Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA'. This has now been corrected in both the PDF and HTML versions of the Article.

Random access quantum information processors using multimode circuit quantum electrodynamics.

Qubit connectivity is an important property of a quantum processor, with an ideal processor having random access-the ability of arbitrary qubit pairs to interact directly. This a challenge with superconducting circuits, as state-of-the-art architectures rely on only nearest-neighbor coupling. Here, we implement a random access superconducting quantum information processor, demonstrating universal operations on a nine-qubit memory, with a Josephson junction transmon circuit serving as the central processor. The quantum memory uses the eigenmodes of a linear array of coupled superconducting resonators. We selectively stimulate vacuum Rabi oscillations between the transmon and individual eigenmodes through parametric flux modulation of the transmon frequency. Utilizing these oscillations, we perform a universal set of quantum gates on 38 arbitrary pairs of modes and prepare multimode entangled states, all using only two control lines. We thus achieve hardware-efficient random access multi-qubit control in an architecture compatible with long-lived microwave cavity-based quantum memories.

Iodine losses in iodised salt following different storage methods.

Iodine retention in three types of iodised salt viz., powdered salt, white crystal and brown crystal salt was estimated at an interval of 15 days following commonly practised storage methods i.e., glass jar with lid, plastic jar with lid, earthernware pot with lid, cut open salt packet and salt pack as it is. Highest percent retention of iodine irrespective of type of salt was noticed in intact salt packet (97.19%). The iodine retention was above 80% in other methods--88.41% retention in cut open salt packet, 84.72% in glass jar, 82.86% in earthern pot and 80.85% in plastic jar. Powdered salt had maximum iodine retention (91.16%) followed by brown crystal salt (84.24%) and white crystal salt (76.71%). Even though the iodine content was found to decrease during storage, the powdered salt and brown crystal salt had iodine in the recommended level. On the contrary, white crystal salt contained only half (7 ppm) that recommended at the retail level (15 ppm).