Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir...
-
Upload
beryl-austin -
Category
Documents
-
view
227 -
download
1
Transcript of Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir...
![Page 1: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/1.jpg)
Nano-sized electromagnetic source on the principles of Free
Electron Lasers
K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko
![Page 2: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/2.jpg)
The main principle of Free Electron Laser (FEL) operation
The work produced by electromagnetic wave on the electron:
Electron trajectory
Electromagnetic field
![Page 3: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/3.jpg)
Cherenkov synchronism condition:
Slowing down systems (TWT, BWO, Cherenkov Lasers: resonators and waveguides change electromagnetic wave properties and decrease it phase velocity,
Destructive interference diminishes A. So, bunching of electron beam is necessary.
Structure factor:
![Page 4: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/4.jpg)
Pump wave:
Trajectory perturbation by pump wave
Induced by the pump wave perturbation of velocity
![Page 5: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/5.jpg)
CARBON NANOTUBE –quasi-one-dimensional carbon macromolecula
Graphene crystalline lattice SWCNT (m,n)
Rc=ma1+na2(m,0) for zigzag CNT(m,m) for armchair CNT
![Page 6: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/6.jpg)
Unrolled circumferential vectors c for a (4,4) armchair nanotube (blackarrow), a (4,0) zigzag nanotube (blue arrow) and a chiral (4,2) nanotube (red arrow) areshown on a graphene plane. a1 and a2 are the unit cell vectors of graphene. The chiralangle and the translational periodicity vector ` of the (4,2) nanotube (green arrow)are also shown. Dashed lines indicate the area spanned by c and ` which correspondsto the unrolled unit cell of the (4,2) nanotube.
![Page 7: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/7.jpg)
Structural parameters and isogonal point group of nanotubes . d is the tube diameter, n is the greatest common divisor of (n1,n2), and q is the number of carbonhexagons (2 C atoms) per unit cell. a0 is the in-plane lattice constant of graphite.
![Page 8: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/8.jpg)
(8,0), (8,2), (8,4), and (8,8) nanotubes with 32, 56, 112, and 32 atoms in the unit cell (indicated in black), respectively.
![Page 9: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/9.jpg)
Some exceptional properties of nanotubes and conventional materials for comparison.(P. G. Collins and P. Avouris, \Nanotubes for electronics", Sci. Am. 283, 62 (2000))
![Page 10: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/10.jpg)
NanoelectromagneticsComplex-valued slow-wave coefficient for
a polar-symmetric surface wave
1E-8 1E-7 1E-6 1E-5 1E-4 1E-3 0,01
10-2
100
102
104 1: Re()2: -Re()/Im()
CN (9,0)
2
1
kb
1 THz 100 THz
b=0.142 nm is the C-C bond length
|Im()| << Re()
k k
h h ih
Dispersionlesssurface wave nanowaveguidein the IR range
![Page 11: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/11.jpg)
Light emission in CNTs
EELECTRIC-FIELD-INDUCED LECTRIC-FIELD-INDUCED HEATING OF THE ELECTRON GASHEATING OF THE ELECTRON GASO. Kibis, M. Portnoi, Carbon nanotubes: A new type of emitter in the terahertz range, Technical Physics Letters. V.31. p. 671 (2005)
IMPACT IONIZATIONIMPACT IONIZATION
J. Chen, V. Perebeinos, M. Freitag, J. Tsang, Q. Fu, Jie Liu, Ph. Avouris, Bright Infrared Emission from Electrically Induced Excitons in Carbon Nanotubes, Science 2005, Vol. 310. no. 5751, pp. 1171 - 1174
CHERENKOV RADIATION CHERENKOV RADIATION MECHANISMMECHANISMK. Batrakov, P. Kuzhir, S. Maksimenko, Radiative instability of electron beams in carbon nanotubes, Proceedings of SPIE, V. 6328 “Nanomodeling II”, p. 63280Z (2006)
![Page 12: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/12.jpg)
Interaction between electron beam and produced electromagnetic wave leads to electron beam modulation. This process can be described by self-consistent system for electromagnetic field:
and for electrons:
Properties of nanotubes useful for generation by electron beam
1) Large length of electrons ballistic transport (~1 – 10 micron);2) Large current density (to 1010 A/cm2) [M. Radosavljevi´c, J. Lefebvre, and A. T. Johnson, “High-field electrical transport and breakdown in bundles of single-wall carbon nanotubes”, Phys. Rev. B 64, 241 307® (2001),S.-B. Lee, K. B. K. Teo, L. A. W. Robinson, A. S. Teh, M. Chhowalla,et al., J. Vac. Sci. Technol. B 20, 2773 (2002)].
![Page 13: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/13.jpg)
Dispersion equation
Emission term
Absorptionterm
electron group velocity in nanotube
![Page 14: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/14.jpg)
If width of emission line exceeds the magnitude ofquantum recoil, then traditional form of second-order Cherenkov resonance is realized:
Otherwise, quantum recoil contributes to resonance condition.
![Page 15: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/15.jpg)
Gain is extremely large as compared with the gain
per unit length for macro-devices
Boundary conditions on nanotube tips and dispersion equations give threshold condition and instability increment
Threshold current and instability increment of generation
![Page 16: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/16.jpg)
Radiation generationis already possible at the current stage of nanotechnologies
development.
![Page 17: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/17.jpg)
Method for the instability control
The points of maximum group velocity and respectively low excitation energy can be advantageous for lasing. In the point of group velocity extremum the negative influence of the beam energy spread is smaller, and therefore more electrons interact with the wave: the radiation effectiveness can be increased. It is also possible to intensify the effect of radiation instability in nanotube due to the generation in the region of small effective mass of quasiparticle.
![Page 18: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/18.jpg)
Compensation of electron beam spread
Extremum of group velocity
Dispersion equation
Then, expansion near this point gives
So, negative influence of beam spread can be reduced.
![Page 19: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/19.jpg)
CONCLUSION:What has been done to the moment?
Thus, the generation of the stimulated radiation by electron beams in nanotubes is predicted.
The dispersion equations of the electron beam instability and threshold conditions for stimulated radiation are derived and studied.
The analysis of the threshold conditions shows realizability
of the CNT-based molecular TWT at the current CNT technology development
![Page 20: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/20.jpg)
THANK YOU
FOR ATTENTION!
![Page 21: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/21.jpg)
TU/eEindhovenJ.Havercort
PENN S TATE
Department of Engineering Science and Mechanics
I N ST I T U T F U R F E ST K O R P E R P H Y SI K
: :Usikov InstituteFor Radiophysics And Electronics Ukraine,Kharkov
A.Lakhtakia
J. Herrmann, I.Hertel
A.Hoffmann,D.Bimberg
O.YevtushenkoN LedentsovI Krestnikov
Universitaires Notre-Dame de la Paix NAMUR, BELGIUMPh. Lambin
Boreskov Institute of Catalysis SB RASNovosibirsk
Ecole Polytechnique Federale de Lausanne Switzerland L. Forro
Chalmers University of Technology, Sweden, E. Campbell
V Kuznetsov
LABORATOIRE DE PHYSIQUE DE LA MATIERE CONDENSEEG. BOSSIS
Laboratory National des Champs Magnetiques PulsesJ. Galibert
Collaboration of the Institute of Nuclear Problems of Belarusian State University in the field of NANOSCIENCE
etceteras
![Page 22: Nano-sized electromagnetic source on the principles of Free Electron Lasers K.G.Batrakov, P.P.Kuzhir S.A.Maksimenko.](https://reader036.fdocuments.net/reader036/viewer/2022062721/56649f225503460f94c3aa16/html5/thumbnails/22.jpg)