Thermal relaxation time and photothermal optomechanical force in sliced photonic crystal silicon nanobeams.

Optomechanical devices based on sliced silicon photonic crystal nanobeams could have several use cases in future quantum technologies, especially as quantum transducers between different quantum systems. To create the required pure mechanical states at low temperatures, an understanding of photon absorption, thermal relaxation, and the associated photothermal force is crucial. Here, we characterize the strength of the photothermal force in sliced silicon nanobeam resonators.

Athletic identity affects prevalence and disclosure of emotional abuse in Finnish athletes.

The present study offers novel insight into the topic of experienced and observed emotional abuse by researching factors that affect athletes' responses to emotional abuse by coaches. The research aimed to explore three main questions: (1) whether athletic identity was associated with the prevalence of emotionally abusive coaching practices, and (2) disclosure of emotional abuse, and (3) whether demographic variations existed in the frequency of emotional abuse, athletic identity, and disclosure of the abuse. Study participants who filled in an anonymous digital survey consisted of athletes from elite to leisure levels living in Finland ( = 3687, aged 12-80, gender 61% female, 37.

A Rare Case of an Inguinal Hernia-Containing (Extraperitoneal) Ureter.

BACKGROUND Ureteroinguinal hernias are exceptionally rare and are seldom diagnosed in the preoperative setting. There are 2 classifications of this type of hernia: paraperitoneal and extraperitoneal. CASE REPORT We report a case of a 67-year-old man who presented with urinary symptoms and a reducible right inguinal hernia.

Roadmap on quantum nanotechnologies.

Quantum phenomena are typically observable at length and time scales smaller than those of our everyday experience, often involving individual particles or excitations. The past few decades have seen a revolution in the ability to structure matter at the nanoscale, and experiments at the single particle level have become commonplace. This has opened wide new avenues for exploring and harnessing quantum mechanical effects in condensed matter.

State Preparation and Tomography of a Nanomechanical Resonator with Fast Light Pulses.

Pulsed optomechanical measurements enable squeezing, nonclassical state creation, and backaction-free sensing. We demonstrate pulsed measurement of a cryogenic nanomechanical resonator with record precision close to the quantum regime. We use these to prepare thermally squeezed and purified conditional mechanical states, and to perform full state tomography.

Nonlinear cavity optomechanics with nanomechanical thermal fluctuations.

Although the interaction between light and motion in cavity optomechanical systems is inherently nonlinear, experimental demonstrations to date have allowed a linearized description in all except highly driven cases. Here, we demonstrate a nanoscale optomechanical system in which the interaction between light and motion is so large (single-photon cooperativity C≈10) that thermal motion induces optical frequency fluctuations larger than the intrinsic optical linewidth. The system thereby operates in a fully nonlinear regime, which pronouncedly impacts the optical response, displacement measurement and radiation pressure backaction.

A dressed spin qubit in silicon.

Coherent dressing of a quantum two-level system provides access to a new quantum system with improved properties-a different and easily tunable level splitting, faster control and longer coherence times. In our work we investigate the properties of the dressed, donor-bound electron spin in silicon, and assess its potential as a quantum bit in scalable architectures. The two dressed spin-polariton levels constitute a quantum bit that can be coherently driven with an oscillating magnetic field, an oscillating electric field, frequency modulation of the driving field or a simple detuning pulse.

Vibration-induced electrical noise in a cryogen-free dilution refrigerator: Characterization, mitigation, and impact on qubit coherence.

Cryogen-free low-temperature setups are becoming more prominent in experimental science due to their convenience and reliability, and concern about the increasing scarcity of helium as a natural resource. Despite not having any moving parts at the cold end, pulse tube cryocoolers introduce vibrations that can be detrimental to the experiments. We characterize the coupling of these vibrations to the electrical signal observed on cables installed in a cryogen-free dilution refrigerator.

Electrically controlling single-spin qubits in a continuous microwave field.

Large-scale quantum computers must be built upon quantum bits that are both highly coherent and locally controllable. We demonstrate the quantum control of the electron and the nuclear spin of a single (31)P atom in silicon, using a continuous microwave magnetic field together with nanoscale electrostatic gates. The qubits are tuned into resonance with the microwave field by a local change in electric field, which induces a Stark shift of the qubit energies.

Bell's inequality violation with spins in silicon.

Bell's theorem proves the existence of entangled quantum states with no classical counterpart. An experimental violation of Bell's inequality demands simultaneously high fidelities in the preparation, manipulation and measurement of multipartite quantum entangled states, and provides a single-number benchmark for the performance of devices that use such states for quantum computing. We demonstrate a Bell/ Clauser-Horne-Shimony-Holt inequality violation with Bell signals up to 2.

A two-qubit logic gate in silicon.

Quantum computation requires qubits that can be coupled in a scalable manner, together with universal and high-fidelity one- and two-qubit logic gates. Many physical realizations of qubits exist, including single photons, trapped ions, superconducting circuits, single defects or atoms in diamond and silicon, and semiconductor quantum dots, with single-qubit fidelities that exceed the stringent thresholds required for fault-tolerant quantum computing. Despite this, high-fidelity two-qubit gates in the solid state that can be manufactured using standard lithographic techniques have so far been limited to superconducting qubits, owing to the difficulties of coupling qubits and dephasing in semiconductor systems.

Quantifying the quantum gate fidelity of single-atom spin qubits in silicon by randomized benchmarking.

Building upon the demonstration of coherent control and single-shot readout of the electron and nuclear spins of individual (31)P atoms in silicon, we present here a systematic experimental estimate of quantum gate fidelities using randomized benchmarking of 1-qubit gates in the Clifford group. We apply this analysis to the electron and the ionized (31)P nucleus of a single P donor in isotopically purified (28)Si. We find average gate fidelities of 99.

Storing quantum information for 30 seconds in a nanoelectronic device.

The spin of an electron or a nucleus in a semiconductor naturally implements the unit of quantum information--the qubit. In addition, because semiconductors are currently used in the electronics industry, developing qubits in semiconductors would be a promising route to realize scalable quantum information devices. The solid-state environment, however, may provide deleterious interactions between the qubit and the nuclear spins of surrounding atoms, or charge and spin fluctuations arising from defects in oxides and interfaces.

An addressable quantum dot qubit with fault-tolerant control-fidelity.

Exciting progress towards spin-based quantum computing has recently been made with qubits realized using nitrogen-vacancy centres in diamond and phosphorus atoms in silicon. For example, long coherence times were made possible by the presence of spin-free isotopes of carbon and silicon. However, despite promising single-atom nanotechnologies, there remain substantial challenges in coupling such qubits and addressing them individually.

Single-shot readout and relaxation of singlet and triplet states in exchange-coupled 31P electron spins in silicon.

We present the experimental observation of a large exchange coupling J ≈ 300 μeV between two (31)P electron spin qubits in silicon. The singlet and triplet states of the coupled spins are monitored in real time by a single-electron transistor, which detects ionization from tunnel-rate-dependent processes in the coupled spin system, yielding single-shot readout fidelities above 95%. The triplet to singlet relaxation time T(1) ≈ 4 ms at zero magnetic field agrees with the theoretical prediction for J-coupled 31P dimers in silicon.

Excitation of single quasiparticles in a small superconducting Al island connected to normal-metal leads by tunnel junctions.

We investigate the dynamics of individual quasiparticle excitations on a small superconducting aluminum island connected to normal metallic leads by tunnel junctions. We find the island to be free of excitations within the measurement resolution. This allows us to show that the residual heating, which typically limits experiments on superconductors, has an ultralow value of less than 0.

Micrometre-scale refrigerators.

A superconductor with a gap in the density of states or a quantum dot with discrete energy levels is a central building block in realizing an electronic on-chip cooler. They can work as energy filters, allowing only hot quasiparticles to tunnel out from the electrode to be cooled. This principle has been employed experimentally since the early 1990s in investigations and demonstrations of micrometre-scale coolers at sub-kelvin temperatures.

[Treatment of mandibular fracture].

Diagnosis of mandibular fracture is usually obvious, but may in unclear cases require several imagings. Even a fracture with good position will require follow-up. Treatment can usually be conducted systematically within the following day.

Interactions between local anesthetics and lipid dispersions studied with liposome electrokinetic capillary chromatography.

In the case of local anesthetic intoxication, intravenous administration of lipid-based Intralipid dispersion (Fresenius Kabi) can be used for the entrapment of hydrophobic drugs. Our long-term aim is to develop a sensitive, efficient, and non-harmful lipid-based formulation to specifically trap harmful substances. In this study liposome electrokinetic capillary chromatography (LEKC) was used to study the interactions between local anesthetics and Intralipid or liposome dispersions.

Interactions of fusidic acid and elongation factor G with lipid membranes.

Fusidic acid (FA) is a potent antibiotic and blocks the protein synthesis by binding to elongation factor G (EF-G) directly. Here we hypothesized that the antibiotic activity of FA would be potentiated by several orders of magnitude if both FA and EF-G would be residing in the lipid membranes and, hence, the probability of interaction would transform from three-dimensional to two-dimensional. Such detailed information could lead to more effective therapeutic interventions if they are understood on a molecular level.

The copolymer of epsilon-caprolactone-lactide and tricalcium phosphate does not enhance bone growth in mandibular defect of sheep.

In the field of craniomaxillofacial and orthopaedic surgery there is a constant need for bone or bone substitute. At the present, the most effective way to enhance bone healing clinically is to use autogenous bone grafts. The problems associated with the use of these autografts are donor site morbidity, limited supply and need for a second operative site.

Endothelial L-selectin ligands in sinus mucosa during chronic maxillary rhinosinusitis.

Rationale: Chronic rhinosinusitis is characterized by persistent inflammation of the nasal and paranasal mucosa with numerous emigrated leukocytes. L-selectin on leukocytes and its endothelial glycosylated ligands initiate organ-specific leukocyte infiltration into inflamed tissues.

Objectives: The purpose of this study was to evaluate the endothelial expression of functionally active endothelial L-selectin ligands, sulfated sialyl Lewis x, in maxillary sinus mucosa from patients with chronic rhinosinusitis and from normal control subjects.

Tissue reactions of subcutaneously implanted mixture of epsilon-caprolactone-lactide copolymer and tricalcium phosphate. An electron microscopic evaluation in sheep.

Biodegradable polymers, mainly derivates of alpha-hydroxy acids, are widely used today in oral- and maxillofacial surgery, orthopedics, and other fields of surgery. These biomaterials are well tolerated by living tissue and fracture fixation devices made of polylactic or polyglycolic acid are clinically widely used today. Still, there are some problems in application of biodegradable polymers.

Osteodistraction of a previously irradiated mandible with or without adjunctive hyperbaric oxygenation: an experimental study in rabbits.

The purpose of this study was to analyse the effects of irradiation and hyperbaric oxygenation (HBO) on mandibular osteodistraction (OD). Eighteen rabbits were divided into three groups: 1. Irradiation (R), 2.