Quantum lithography
Encyclopedia
Quantum lithography is a type of photolithography
, which exploits non-classical properties of the photons, such as quantum entanglement
, in order to achieve superior performance over ordinary classical lithography. Quantum lithography is closely related to the fields of quantum imaging
, quantum metrology
, and quantum sensing. The effect exploits the quantum mechanical state of light called the NOON state
. Quantum lithography was invented at Jonathan P. Dowling's group at JPL, and has been studied by a number of groups.
Of particular importance, quantum lithography can beat the classical Rayleigh criterion for the diffraction
limit. Classical photolithography
has an optical imaging
resolution that cannot be smaller than the wavelength of light used. For example, in the use of photolithography
to mass produce computer chips, it is desirable to produce smaller and smaller features on the chip, which classically requires moving to smaller and smaller wavelengths (ultraviolet and x-ray), which entails exponentially greater cost to produce the optical imaging systems at these extremely short optical wavelengths.
Quantum lithography exploits the quantum entanglement
between specially prepared photons in the NOON state
to achieve the smaller resolution without the requirement of shorter wavelengths. For example, a beam of red photons, entangled ten at a time in the NOON state, would have the same resolving power as a beam of x-ray photons.
The field of quantum lithography is in its infancy, and although experimental proofs of principal have been carried out using the Hong–Ou–Mandel effect, it is still a long way from commercial application.
Photolithography
Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...
, which exploits non-classical properties of the photons, such as quantum entanglement
Quantum entanglement
Quantum entanglement occurs when electrons, molecules even as large as "buckyballs", photons, etc., interact physically and then become separated; the type of interaction is such that each resulting member of a pair is properly described by the same quantum mechanical description , which is...
, in order to achieve superior performance over ordinary classical lithography. Quantum lithography is closely related to the fields of quantum imaging
Quantum imaging
Quantum imaging,, is a new sub-field of quantum optics that exploits quantum correlations such as quantum entanglement of the electromagnetic field in order to image objects with a resolution or other imaging criteria that is beyond what is possible in classical optics. Examples of quantum imaging...
, quantum metrology
Quantum metrology
Quantum metrology is the study of making high-resolution and highly sensitive measurements of physical parameters using quantum theory to describe the physical systems, particularly exploiting quantum entanglement...
, and quantum sensing. The effect exploits the quantum mechanical state of light called the NOON state
NOON state
A NOON state is a quantum-mechanical many-body entangled state:A NOON state is a quantum-mechanical many-body entangled state:A NOON state is a quantum-mechanical many-body entangled state:...
. Quantum lithography was invented at Jonathan P. Dowling's group at JPL, and has been studied by a number of groups.
Of particular importance, quantum lithography can beat the classical Rayleigh criterion for the diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...
limit. Classical photolithography
Photolithography
Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...
has an optical imaging
Optical imaging
Optical imaging is an imaging technique.Optics usually describes the behavior of visible, ultraviolet, and infrared light used in imaging.Because light is an electromagnetic wave, similar phenomena occur in X-rays, microwaves, radio waves. Chemical imaging or molecular imaging involves inference...
resolution that cannot be smaller than the wavelength of light used. For example, in the use of photolithography
Photolithography
Photolithography is a process used in microfabrication to selectively remove parts of a thin film or the bulk of a substrate. It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical "photoresist", or simply "resist," on the substrate...
to mass produce computer chips, it is desirable to produce smaller and smaller features on the chip, which classically requires moving to smaller and smaller wavelengths (ultraviolet and x-ray), which entails exponentially greater cost to produce the optical imaging systems at these extremely short optical wavelengths.
Quantum lithography exploits the quantum entanglement
Quantum entanglement
Quantum entanglement occurs when electrons, molecules even as large as "buckyballs", photons, etc., interact physically and then become separated; the type of interaction is such that each resulting member of a pair is properly described by the same quantum mechanical description , which is...
between specially prepared photons in the NOON state
NOON state
A NOON state is a quantum-mechanical many-body entangled state:A NOON state is a quantum-mechanical many-body entangled state:A NOON state is a quantum-mechanical many-body entangled state:...
to achieve the smaller resolution without the requirement of shorter wavelengths. For example, a beam of red photons, entangled ten at a time in the NOON state, would have the same resolving power as a beam of x-ray photons.
The field of quantum lithography is in its infancy, and although experimental proofs of principal have been carried out using the Hong–Ou–Mandel effect, it is still a long way from commercial application.