bak

Author: cirosantilli

condensed-matter-physics.bigb

@@ -914,6 +914,10 @@ Mentioned at: <video Quantum Computing with Light by Quantum Light University of
 = Metallic
 {synonym}
 
+= Field electron emission
+{parent=Metal}
+{wiki}
+
 = Alloy
 {parent=Metal}
 {wiki}

electronics.bigb

@@ -628,6 +628,15 @@ It resists to change in <electric current>. Well seen at: <video LC circuit by E
 {parent=Resistor}
 {wiki=Electrical_resistance_and_conductance}
 
+= Drude model
+{c}
+{parent=Electrical resistance}
+{wiki}
+
+= Free electron model
+{parent=Drude model}
+{wiki}
+
 = Ohm
 {c}
 {parent=Electrical resistance}

microscopy.bigb

@@ -115,6 +115,10 @@ Each one of them appears in the image in a random rotated view, so given enough
 {title=A <cryoEM> image}
 {description=This is the type of image that you get out of a raw CryoEM experiment.}
 
+\Video[https://youtu.be/dGeMaxMb9Lw?t=581]
+{title=The structure of our cells by Matteo Allegretti}
+{description=The start is useless. But the end at this timestamp shows an interesting technique where they actually cut up cells in fine slices and image them, that's cool.}
+
 = Fluorescence microscope
 {parent=Type of microscopy}
 {wiki}

photon.bigb

@@ -594,10 +594,16 @@ First live example: https://en.wikipedia.org/wiki/IKAROS
 \Image[https://upload.wikimedia.org/wikipedia/commons/thumb/1/17/IKAROS_IAC_2010.jpg/568px-IKAROS_IAC_2010.jpg]
 {title=A 1:64 scale model of the IKAROS spacecraft}
 
-= Single photon production and detection experiments
+= Single photon production and detection
 {parent=Photon}
 {tag=Photonics equipment}
 
+= Single photon production and detection experiments
+{synonym}
+
+= Single photon
+{synonym}
+
 You can't get more direct than this in terms of proving that <photons> exist!
 
 The particular case of the <double-slit experiment> will be discussed at: <single particle double slit experiment>.
@@ -627,8 +633,14 @@ Bibliography:
 * https://youtu.be/Vt84rSJa7VI?t=721 <Poincaré sphere>
 }
 
+= Single photon production
+{parent=Single photon production and detection}
+
+= Single photon source
+{synonym}
+
 = Spontaneous parametric down-conversion
-{parent=Single photon production and detection experiments}
+{parent=Single photon production}
 {title2=SPDC}
 {wiki}
 
@@ -660,8 +672,43 @@ Very short whiteboard video by Peter Mosley from the University of Bath, but it'
 One interesting thing he mentions is that you could get single photons by making your sunglasses thicker and thicker to reduce how many photons pass, but one big downside problem is that then you don't know when the photon is going to come through, that becomes essentially random, and then you can't use this technique if you need two photons at the same time, which is often the case, see also: <two photon interference experiment>.
 }
 
+= Single photon detection
+{parent=Single photon production and detection}
+
+= Detect single photon
+{synonym}
+
+= Photomultiplier
+{parent=Single photon detection}
+{wiki}
+
+= Photomultiplier tube
+{parent=Photomultiplier}
+{tag=Photonics equipment}
+{wiki}
+
+Can be used to <single photon production and detection experiments>[detect single photons].
+
+<Richard Feynman> likes them, he describes the tube at <Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979)> at one point.
+
+It uses the <photoelectric effect> multiple times to produce a chain reaction. In particular, as mentioned at https://youtu.be/5V8VCFkAd0A?t=74 from <video Using a Photomultiplier to Detect Single Photons by Huygens Optics> this means that the device has a lowest sensitive light frequency, beyond which <photons> don't have enough energy to eject any <electrons>. 
+
+\Image[https://upload.wikimedia.org/wikipedia/commons/3/36/Pmside.jpg]
+
+\Video[https://www.youtube.com/watch?v=5V8VCFkAd0A]
+{title=Using a <Photomultiplier> to <Detect Single Photons> by <#Huygens Optics>}
+{description=2024. Wow this dude is amazing as usual. Unfortunately he's not using a <single photon source>, just an <LED>.}
+
+= Silicon photomultiplier
+{parent=Photomultiplier}
+{wiki}
+
+Here is a vendor showcasing their device. They claim in that video that a single photon is produced and detected:
+
+Concrete device described at: <video How to use an SiPM - Experiment Video by SensLTech (2018)>.
+
 = Two photon interference experiment
-{parent=Single photon production and detection experiments}
+{parent=Single photon production and detection}
 {wiki}
 
 The basic experiment for a <photonic quantum computer>.
@@ -688,29 +735,6 @@ Animation of in-silicon single photon device with brief description of emitting
 {title=Building a Quantum Computer Out of Light by whentheappledrops (2014)}
 {description=Yada yada yada, then at https://youtu.be/ofg335d3BJ8?t=341 shows optical table and it starts being worth it. Jacques Carolan from the University of Bristol goes through their setup which injects 5 photons into a 21-way experiment.}
 
-= Photomultiplier
-{parent=Single photon production and detection experiments}
-{wiki}
-
-= Photomultiplier tube
-{parent=Photomultiplier}
-{tag=Photonics equipment}
-{wiki}
-
-Can be used to <single photon production and detection experiments>[detect single photons].
-
-<Richard Feynman> likes them, he describes the tube at <Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979)> at one point.
-
-It uses the <photoelectric effect> multiple times to produce a chain reaction.
-
-= Silicon photomultiplier
-{parent=Photomultiplier}
-{wiki}
-
-Here is a vendor showcasing their device. They claim in that video that a single photon is produced and detected:
-
-Concrete device described at: <video How to use an SiPM - Experiment Video by SensLTech (2018)>.
-
 = Squeezed state of light
 {parent=Photon}
 {tag=Squeezed coherent state}

physics.bigb

@@ -211,6 +211,9 @@ This is different from classic waves where energy is proportional to intensity,
 {parent=Energy}
 {wiki}
 
+= Potential barrier
+{parent=Potential energy}
+
 = Kinetic energy
 {parent=Energy}
 {wiki}

statistical-physics.bigb

@@ -17,10 +17,31 @@ This theory attempts to deduce/explain properties of matter such as the <equatio
 {parent=Statistical physics}
 {wiki}
 
-= Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics
+= Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Dirac statistics
 {c}
 {parent=Statistical physics}
 
+= Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics
+{synonym}
+
+<Maxwell-Boltzmann statistics>, <Bose-Einstein statistics> and <Fermi-Dirac statistics> all describe how energy is distributed in different physical systems at a given temperature.
+
+For example, <Maxwell-Boltzmann statistics> describes how the speeds of particles are distributed in an <ideal gas>.
+
+The <temperature> of a gas is only a statistical average of the total <energy> of the gas. But at a given temperature, not all particles have the exact same speed as the average: some are higher and others lower than the average.
+
+For a large number of particles however, the fraction of particles that will have a given speed at a given temperature is highly deterministic, and it is this that the distributions determine.
+
+One of the main interest of learning those statistics is determining the probability, and therefore average speed, at which some event that requires a minimum energy to happen happens. For example, for a <chemical reaction> to happen, both input molecules need a certain speed to overcome the <potential barrier> of the reaction. Therefore, if we know how many particles have energy above some threshold, then we can estimate the speed of the reaction at a given temperature.
+
+The three distributions can be summarized as:
+* <Maxwell-Boltzmann statistics>: statistics without considering <quantum> statistics. It is therefore only an approximation. The other two statistics are the more precise quantum versions of <Maxwell-Boltzmann> and tend to it at high <temperatures> or low concentration. Therefore this one works well at high temperatures or low concentrations.
+* <Bose-Einstein statistics>: <quantum> version of <Maxwell-Boltzmann statistics> for <bosons>
+* <Fermi-Dirac statistics>: <quantum> version of <Maxwell-Boltzmann statistics> for <fermions>. Sample system: electrons in a metal, which creates the <free electron model>. Compared to <Maxwell-Boltzmann statistics>, this explained many important experimental observations such as the <specific heat capacity> of metals. A very cool and concrete example can be seen at https://youtu.be/5V8VCFkAd0A?t=1187 from <video Using a Photomultiplier to Detect Single Photons by Huygens Optics> where spontaneous <field electron emission> would follow <Fermi-Dirac statistics>. In this case, the electrons with enough energy are undesired and a source of <noise> in the experiment.
+
+\Image[https://upload.wikimedia.org/wikipedia/commons/d/d8/Quantum_and_classical_statistics.png]
+{title=<Maxwell-Boltzmann> vs Bose-Einstein vs Fermi-Dirac statistics}
+
 A good conceptual starting point is to like the example that is mentioned at <The Harvest of a Century by Siegmund Brandt (2008)>.
 
 Consider a system with 2 particles and 3 states. Remember that:
@@ -113,22 +134,23 @@ Therefore, all the possible way to put those two particles in three states are f
   | A
   | A
 
-Both <Bose-Einstein statistics> and <Fermi-Dirac statistics> tend to the <Maxwell-Boltzmann distribution> in the limit of either:
-* high <temperature>
-* low concentrations
-TODO: show on forumulas. TODO experimental data showing this. Please.....
-
 = Maxwell-Boltzmann distribution
 {c}
-{parent=Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics}
+{parent=Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Dirac statistics}
 {title2=MB distribution}
 {wiki=Maxwell–Boltzmann_distribution}
 
+\Image[https://en.wikipedia.org/wiki/File:Maxwell-Boltzmann_distribution_1.png]
+{title=Maxwell-Boltzmann distribution for three different <temperatures>}
+
 = Maxwell-Boltzmann statistics
 {c}
 {parent=Maxwell-Boltzmann distribution}
 {wiki}
 
+= Maxwell-Boltzmann
+{synonym}
+
 = Experimental verification of the Maxwell-Boltzmann distribution
 {parent=Maxwell-Boltzmann distribution}
 
@@ -164,7 +186,7 @@ https://edisciplinas.usp.br/pluginfile.php/48089/course/section/16461/qsp_chapte
 * <reaction rate> as it calculates how likely it is for particles to overcome the <activation energy>
 
 = Quantum statistics
-{parent=Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics}
+{parent=Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Dirac statistics}
 {{wiki=Particle_statistics#Quantum_statistics}}
 
 = Bose-Einstein statistics
@@ -173,15 +195,18 @@ https://edisciplinas.usp.br/pluginfile.php/48089/course/section/16461/qsp_chapte
 {title2=BE statistics}
 {wiki=Bose–Einstein_statistics}
 
-Start by looking at: <Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics>.
+Start by looking at: <Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Dirac statistics>.
 
 = Fermi-Dirac statistics
 {c}
 {parent=Quantum statistics}
 {title2=FD statistics}
 {wiki=Fermi–Dirac_statistics}
 
-Start by looking at: <Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Diract statisics>.
+= Fermi-Dirac
+{synonym}
+
+Start by looking at: <Maxwell-Boltzmann vs Bose-Einstein vs Fermi-Dirac statistics>.
 
 = Quantum statistical mechanics
 {parent=Fermi-Dirac statistics}
@@ -293,6 +318,9 @@ I think these are the ones where $\Delta H \times \Delta S > 0$, i.e. <enthalpy>
 {parent=Equation of state}
 {wiki}
 
+= Ideal gas
+{synonym}
+
 = Monatomic gas
 {parent=Ideal gas law}
 {wiki}

technology.bigb

@@ -454,6 +454,9 @@ TODO how close does it get to Shannon's limit?
 = Signal-to-noise
 {synonym}
 
+= Noise
+{synonym}
+
 = Quantum information
 {parent=Information}
 {wiki}