  We study experimentally work fluctuations in a Szilard engine that extracts
work from information encoded as the occupancy of an electron level in a
semiconductor quantum dot. We show that as the average work extracted per bit
of information increases towards the Landauer limit $k_BT \ln 2$, the work
fluctuations decrease in accordance with the work fluctuation-dissipation
relation. We compare the results to a protocol without measurement and feedback
and show that when no information is used, the work output and fluctuations
vanish simultaneously contrasting the information-to-energy conversion case
where increasing amount of work is produced with decreasing fluctuations. Our
work highlights the importance of fluctuations in the design of
information-to-work conversion processes.
