Data from: A dissipation-induced superradiant transition in a strontium cavity-QED system
Data files
Abstract
Driven-dissipative many-body systems are ubiquitous in nature and a fundamental resource for quantum technologies. However, they are also complex and hard to model since they cannot be described by the standard tools in equilibrium statistical mechanics. Probing non-equilibrium critical phenomena in pristine setups can illuminate new perspectives on such systems. Here we use an ensemble of cold $^{88}$Sr atoms coupled to a driven high-finesse cavity to study the cooperative resonance fluorescence (CRF) model, a classic driven-dissipative model describing coherently driven dipoles superradiantly emitting light. We observe its non-equilibrium phase diagram characterized by a second-order phase transition. Below a critical drive strength, the atoms quickly reach the so-called superradiant steady-state featuring a macroscopic dipole moment; above the critical point, the atoms undergo persistent Rabi-like oscillations. At longer times, spontaneous emission transforms the second-order transition into a discontinuous first-order transition. Our observations pave the way for harnessing robust entangled states and exploring boundary time crystals in driven-dissipative systems.
https://doi.org/10.5061/dryad.j6q573nrb
Description of the data and file structure
Files are named according to the following naming convention: figASSOCIATED SUBFIGURE.csv. See the explanation below:
[ASSOCIATED SUBFIGURE] references the subfigure of the manuscript where the data is plotted. This repository contains data from fig2, fig3, fig4, and fig5, which are the four figures containing experimental data. All of these figures contain sub-panels which are labeled alphabetically. For example, data from Fig. 2, panel c is referenced by fig2c.
Data in each file is separated into columns. They represent x, y-coordinate value of each data point or corresponding error bars. They are labeled according to the following naming convention: [PARAMETER]_[COORDINATE/ERRORBAR]. See the explanation below:
[PARAMETER] refers to the parameter distinguishing different traces in a subfigure. For example, data from Fig. 2a is characterized by different atom numbers, so N=3.4e3, N=8.2e3, and N=2.1e4 are used to label different datasets with different atom numbers. For completeness, we used \Omega_d/\Omega_c=1.4, $t=9~\mu$s, Quench/Ramp, \Delta_{ca}=0 to represent different Rabi frequencies used, different drive durations, different ways of turning on the drive, and different cavity-atom detunings used in the experiment. For all the simulation results presented in the paper, [PARAMETER] is further appended by _theory.
[COORDINATE/ERRORBAR] denotes the x, y-coordinates of the data or the associated error bars. Concretely, 4 types of data are recorded:
- x: x-coordinate of the data in that trace.
- y: y-coordinate of the data in that trace.
- x_error: error bars associated with each x-data point in that trace.
- y_error: error bars associated with each y-data point in that trace.
The data is expressed in the same units present in the figures. For completeness, we describe the units here:
- Drive Rabi frequency are recorded in
MHz. - Normalized Rabi frequency is dimensionless.
- Spin projection Jz/(N/2) are normalized to
[-1,1]. - Fractional transmission are normalized to
[0,1]. - Drive duration t is recorded in units of
μs.
Below, we describe how error bars are reported:
- All error bars represent the standard error of the mean for the relevant quantity.
- Error bars are reported a separate column and are typically indicated in the header with an
_errorafter the measured value. For example, the error bars for y-coordinate data reported asN=2.1e4_yare labeled with a headerN=2.1e4_y_error.