Figure 4: Pulse length dependence and III–V and Si compatibility.

(a) Readout signal of a 4 μm CuMnAs/GaAs device as a function of the applied write-pulse length at a fixed current density of 1.2 × 10⁷ A cm⁻². Reading is performed with a current density of 1 × 10⁵ A cm⁻², 5 s after the write pulse. The initial linear slope of the dependence (signal per pulse length ratio) is highlighted by the dashed line. Plotted data points are the average over fifteen measurements; error bars represent the standard deviation. (b) Readout signal per write-pulse length obtained from the initial linear slope (see a) as a function of the write current density, for 30 μm CuMnAs/GaP (red), 4 μm CuMnAs/GaAs (black), and 2 μm CuMnAs/GaP (blue) devices. (c) Readout signal as a function of the number of pulses in the train of pulses for the individual pulse length of 250 ps and writing current density 16 × 10⁷ A cm⁻² in a 4 μs CuMnAs/GaAs devices. Plotted data points are the average over fifteen measurements; error bars represent the standard deviation. (d) Multi-level switching in the device fabricated from CuMnAs/Si. Three pulses are applied along the [100] direction followed by three pulses along the [010] direction with current density of 2 × 10⁷ A cm⁻² and pulse length 100 μm. (e) Histogram of the six different states, obtained from 50 repetitions of the 3+3 pulse sequence (bin size is 1.4 mΩ). All measurements were performed at room temperature.