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Plasma potential measurements in a rf inductively coupled oxygen plasma were carried out using an emissive probe with rhenium filaments. Rhenium was chosen because of the remarkable electrical conductivity of its oxide which is 108 times higher than tungsten oxide. Using 75 μm diam filaments hot-wire emissive probe measurements of an oxygen plasma potential were performed in pressures of 3–100 mTorr. Due to surface contaminants, filament conditioning was performed in order to allow electron emission. Analysis of time-averaged current–voltage curves yielded the maximum and minimum of the rf fluctuation in the plasma. Axial profiles of the plasma potential fluctuations at 3.3 mTorr show a nearly linear decrease with the distance from the wall, and demonstrate the feasibility for further investigation of oxygen plasmas using rhenium filaments.

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Running quantum programs is fraught with challenges on on today's noisy intermediate scale quantum (NISQ) devices. Many of these challenges originate from the error characteristics that stem from rapid decoherence and noise during measurement, qubit connections, crosstalk, the qubits themselves, and transformations of qubit state via gates. Not only are qubits not "created equal", but their noise level also changes over time. IBM is said to calibrate their quantum systems once per day and reports noise levels (errors) at the time of such calibration. This information is subsequently used to map circuits to higher quality qubits and connections up to the next calibration point.This work provides evidence that there is room for improvement over this daily calibration cycle. It contributes a technique to measure noise levels (errors) related to qubits immediately before executing one or more sensitive circuits and shows that justin-time noise measurements benefit late physical qubit mappings. With this just-in-time recalibrated transpilation, the fidelity of results is improved over IBM's default mappings, which only uses their daily calibrations. The framework assess two major sources of noise, namely readout errors (measurement errors) and two-qubit gate/connection errors. Experiments indicate that the accuracy of circuit results improves by 3-304% on average and up to 400% with on-the-fly circuit mappings based on error measurements just prior to application execution.