  The face of physics is a function of scale. This widespread phrase is
considered as a universal truth because it reflects the experience of
generations of physicists. Starting from primary school we know that the
physics of macroscopic solid state systems rests on the notion that these
systems consist of a great number of spatially periodic microscopic building
blocks. Thus, it seems to be quite logic to expect the same properties from
geometrically identical macroscopic regions of the same macroscopic system. The
above statement is quite general and it is also known to be valid for the
systems of a reduced dimensionality in the direction, along which they are
macroscopic. However, in this work we report on a macroscopic system, which
does not obey the above postulates and demonstrates specific quantum behaviour
on a macroscopic length. It is conventional quantum Hall system possessing an
asymmetric confining potential in presence of a tilted quantizing magnetic
field. In the direction, along which the system is macroscopic, it demonstrates
the following unusual properties: (i) a spatially-dependent response on a
spatially-homogeneous photo-excitation that implies spontaneous breaking of
translational symmetry (ii) high sensitivity of a local photo-response to the
conditions of macroscopically remote local regions (iii) excitation of whole
system through the excitation of its local region without an appropriate energy
transfer within the system. All these properties imply the electron coherent
length to be as high as the macroscopic sample length. We demonstrate that the
effect revealed opens the door for an energy-free quantum communication on
macroscopic distances.
