A team of Boston University physicists led by Assistant Professor Pritiraj Mohanty have developed a nanomechanical oscillator (essentially a small comb-like structure vibrating between two anchors). The oscillator is comprised of 50 billion atoms (0.0107 milli-meter). When it is oscillated at a frequency of 1.49 GHz (1.49 billion times per second), with an amplitude equal to the size of an atom, the oscillator displays quantum mechanical properties.
In our (classical) macroscopic world, physical constructs (space, time, weight, temperature etc.) are continous in nature. For example, when we move from point A to point B, we are traveling through all points between A and B. Similarly, when we heat a bowl of water, say from 25º to 75º, the temperature of the water rises continuously from 25º to 75º. However, the world of small (typically, less than a nanometer) is dominated by quantum mechanics, where these common-sense rules of continuous change do not apply. All physical parameters at such small scales behave quantum-mechanically, that is, the parameter values increase (or decrease) in discrete (quantum) jumps. It is as if the water temperature can only rise from 25º to 75º by steps of 1º! Fortunately, this quantum step is usually extremely small (of the order of 10^-30), and hence indetectable to the naked eye.
Einstein in his seminal paper in 1905 (on Photoelectric effect) showed that for light to behave as it does, it must come in small energy packets (later) called photons. Soon, scientists such as Heisenberg and Schroedinger developed the new physics of Quantum Mechanics, where everything comes in discrete packets of extremely small size. Under this theory, even space and time are quantized in nature, and at such small scales, particles cannot move continuously from point A to B, but must travel this distance in discrete steps/jumps.
The above phenomenon has already been observed in particles such as electrons and photons. Now the physicists have for the first time observed the above phenomenon at a (comparatively) macroscopic level. In our macroscopic world, we would expect a structure such as the above mentioned oscillator to move smoothly. Instead, it behaves in a peculiar manner: it moves in steps. It is as if instead of rolling smoothly down a hill, a ball is moving as if it is climbing down a staircase.
At the quantum level, energy comes in packets as well. Since the oscillator can only have energy values that come in integral multiples of this quantum packet (you can have 10 packets, or 11 packets, but not 10.5), it moves in steps. Thus we observe (Movie here) a jerky motion by the oscillator.