Imperial physicists have achieved a significant milestone in the world of quantum physics by recreating the famous double-slit experiment in time rather than space.
The groundbreaking experiment, led by Professor Riccardo
Sapienza of the Department of Physics at Imperial College London, involves
firing light through a material that changes its optical properties in
femtoseconds, allowing light to pass through at specific times in quick
succession.
The team’s achievement opens the door to a whole new
spectroscopy capable of resolving the temporal structure of a light pulse on
the scale of one period of the radiation.
The original double-slit experiment, performed in 1801 by
Thomas Young at the Royal Institution, showed that light acts as a wave.
Further experiments revealed that light behaves both as a wave and as
particles, exposing its quantum nature. These experiments had a profound impact
on quantum physics, revealing the dual particle and wave nature of not just
light, but other “particles” including electrons, neutrons, and whole atoms.
In the classic version of the double-slit experiment, light
emerging from the physical slits changes its direction, so the interference
pattern is written in the angular profile of the light. The Imperial team’s
experiment, however, changes the frequency of the light rather than its
direction, altering its color and creating colors of light that interfere with each
other to produce an interference-type pattern.
The material used in the experiment was a thin film of
indium-tin-oxide, the same material used to make most mobile phone screens. The
team used lasers on ultrafast timescales to change the reflectance of the
material, creating the “slits” for light. The material’s response was much
quicker than the team expected, varying its reflectivity in a few femtoseconds.
The team’s achievement is published in Nature Physics, with the lead researcher, Professor Sapienza, saying: “Our experiment reveals more about the fundamental nature of light while serving as a stepping-stone to creating the ultimate materials that can minutely control light in both space and time.”
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The famous double-slit experiment, which showed that light
can behave both as a wave and as a particle. (CREDIT: Creative Commons) |
Co-author Professor Sir John Pendry also commented on the
experiment, saying, “The double time slits experiment opens the door to a whole
new spectroscopy capable of resolving the temporal structure of a light pulse
on the scale of one period of the radiation.”
The team’s experiment holds significant implications for
quantum physics and opens the door to the exploration of new technologies that
could revolutionize our understanding of the nature of light. Furthermore, the
team’s next goal is to explore the phenomenon in a “time crystal,” analogous to
an atomic crystal but where the optical properties vary in time. According to
co-author Professor Stefan Maier, “The concept of time crystals has the
potential to lead to ultrafast, parallelized optical switches.”
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Observation of a spectral diffraction pattern from temporal
double slits. (CREDIT: Nature Physics) |
The Imperial team’s achievement is a groundbreaking
milestone in quantum physics, providing deeper insights into the nature of light
and opening the door to potential applications with metamaterials providing a
new avenue for exploring fundamental physics phenomena like black holes.
In addition to the potential for studying black holes, the
team’s work could also have significant implications for the development of new
technologies. The ability to minutely control light in both space and time
could lead to advancements in fields like telecommunications, computing, and
even medicine.
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Professor Riccardo Sapienza and Sir John Pendry of the
Department of Physics at Imperial College London (CREDIT: ICL) |
Telecommunications is one field where the team’s findings
could have a significant impact. By controlling the timing and frequency of
light, researchers could develop new types of optical switches that are faster
and more efficient than current technologies. This could lead to faster
internet speeds and more reliable data transmission, among other benefits.
The field of computing could also benefit from the team’s
work. By using metamaterials to control the behavior of light, researchers
could develop new types of optical processors that are faster and more
energy-efficient than current electronic processors. This could lead to the
development of computers that are both faster and more energy-efficient, with
the potential to revolutionize the field of computing.
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Now, a team led by Imperial College London physicists has
performed the experiment using ‘slits’ in time rather than space. (CREDIT: ICL) |
In medicine, the ability to control the timing and frequency
of light could lead to the development of new types of diagnostic and
therapeutic tools. For example, researchers could develop new types of imaging
technologies that are more precise and less invasive than current techniques.
They could also use light to precisely target and destroy cancer cells, leading
to more effective cancer treatments with fewer side effects.
The potential applications of the team’s findings are not
limited to these fields, however. Metamaterials have the potential to
revolutionize a wide range of industries, from energy and transportation to
aerospace and defense.
Overall, the Imperial team’s achievement is a significant
milestone in the field of quantum physics, providing deeper insights into the
nature of light and opening the door to the development of new technologies
that could transform our world. With further research, it is likely that
metamaterials will become increasingly important in a wide range of industries,
leading to new advancements and discoveries that we can only begin to imagine.
Reference: Research Paper