Nonequilibrium heat dissipation as a probe for detecting wavefront distortion in microscopy

Although an optical vortex (OV) is a promising means for driving cyclic Brownian dynamics of a small particle, the OV-driven dynamics cannot avoid producing additional nonequilibrium heat dissipation of a few tens of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:msub><a:mi>k</a:mi><a:mtext>B</a:mtext></a:msub><a:mi>T</a:mi></a:mrow></a:math> per cycle due to distortion of a light wavefront. We propose an adaptive wavefront-optimization concept, where minor wavefront distortion in microscopy can be probed by the additional heat dissipation itself. As a result, the additional heat dissipation was suppressed to <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:mrow><b:mo><</b:mo><b:mn>0.6</b:mn><b:mspace width="0.16em"/><b:msub><b:mi>k</b:mi><b:mtext>B</b:mtext></b:msub><b:mi>T</b:mi></b:mrow></b:math>, which makes OVs applicable to examining small nonequilibrium changes in thermodynamic systems. The present approach is expected to become an experimental standard in the nonequilibrium physics field.