Scientists claimed Friday they have designed the "smallest, most accurate" quantum thermometer allowed by the laws of physics.

The theoretical thermometer, made up of just a handful of atoms, could detect the smallest fluctuations in microscopic regions, such as the variations within a biological cell, they reported in the U.S. journal Physical Review Letter.

The device is so small that it exhibits distinctive "quantum" features, according to the research, which was conducted jointly by physicists at Universitat Autonoma de Barcelona in Spain and University of Nottingham in UK.

"Devising sensitive and practical nano-scale thermometers would represent a huge leap forward as such technology would enable a plethora of applications in bioscience, chemistry, physics and in the diagnosis and treatment of many diseases," according to a statement from the authors of the research.

To design the thermometer, the physicists combined thermodynamic tools with quantum metrology, which deals with ultra- precise measures in quantum systems.

In the research, they observed that the device could maintain a constant sensitivity over a wide range of temperatures by sacrificing some of their precision.

In addition, they looked at the maximum accuracy achievable in realistic situations in which the time available for the temperature measurement may be short due to unavoidable experimental limitations.