Quantum levitation - achieving the
impossible: flying trains?
Quantum Magnetic levitation is a process in which a
superconductor can levitate along a magnetic track, or hover in a
certain place, with maximum efficiency. This perplexing physics
phenomena revolves around quantum physics, and more
specifically, the manipulation of the Meissner effect which only
occurs when a material, such as ceramic, is cold enough to behave
like a superconductor.
What exactly are superconductors and the Meissner
effect?
Superconductors are a set of physical properties observed in
certain materials where electrical resistance disappears and
magnetic fields are expelled from the material. Any material
exhibiting these properties is a superconductor.
The Meissner effect is defined as “the expulsion of a magnetic field
from the interior of a material that is in the process of becoming a
superconductor, that is, losing its resistance to the flow of
electrical currents when cooled below a certain temperature, called
the transition temperature, usually close to absolute zero.”
Despite the confusing definition, this concept is able to be
understood as the change of state of a certain material at a given
superconducting transition temperature/critical temperature. The
temperature requirement being nearly absolute zero is not an
exaggeration as the required temperature is approximately -181oc,
which is possible through the use of liquid nitrogen, which is even
colder than this temperature, at 196oc.
This so-called superconducting state change converts normal
conductors to superconductors, meaning that all resistivity of the
material suddenly drops to 0 meaning that minimal energy is lost.
Typical energy loss seen in a copper wire can be observed at home
with a rubber-coated wire, as electricity passes through the copper
wire, the rubber starts to feel warmer. This is due to material
resistivity in which some of the energy is transferred to heat and
that energy is lost, which is not seen in superconductors due to no
material resistivity. These superconductors also repel the magnetic
field and magnetic attraction, making the magnetic fields appear
as they are bouncing off the superconductor and eventually going
around it. This is the core idea in the levitation of a
superconductor.
However, this is only known as a type 1 superconductor, in order
to lead to any form of stability and quantum locking, a type to 2
superconductor has to be formed. Type 2 superconductors are
usually thinner and the main design feature and characteristic is
that there are many impurities present, making some magnetic
field lines pass through it. The points of penetration create a form
of magnetic line vortex, where every magnetic field line around
the area will funnel through it together. However, to go through
the impurities, the magnetic field has to be symmetrical on both
sides, creating theoretical strings going through the type 2
superconductor, locking it in place until moved by an external
force, causing it to glide/hover along the surface of magnets.
Turning futuristic dreams into a reality.
This can be used to create levitating trains, an amazing new way of
transportation. They would take up less space, and they would be
more efficient and sustainable, as they reduce friction that is seen in
standard rolling trains and energy loss. This concept has been utilized
worldwide by engineers in effort to make this a commercialized form
of transport. Even though this seems like an extremely unlikely
futuristic idea, this is seen in many countries in Asia such as Japan and
South Korea
In conclusion, quantum magnetic levitation is a very useful concept,
both for sustainability, and in everyday life, along with more efficient
modes of transportation increasing industrial efficiency and speeds of
transportation.