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Some References:

Some References:

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Some References:

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  1. Some References: Colloids – A lot of what I presented is in -"Thermodynamics and Hydrodynamics of Hard Spheres; the role of gravity.", P. M. Chaikin, in Soft and Fragile Matter, Nonequilibrium Dynamics, Metastability and Flow, ed. By M. E. Cates and M. R. Evans, (Institute of Physics Publishing, London, 2000) and there are more general references and it is a good volume. Some of our stuff: Z. Cheng, W.B. Russel, and P.M. Chaikin "Controlled growth of hard-sphere colloidal crystals", Nature 401, 893 - 895 (1999). "Crystallization Kinetics of Hard Spheres in Microgravity in the Coexistence Regime: Interactions between Growing Crystallites", Zhengdong Cheng, P. M. Chaikin, Jixiang Zhu, W. B. Russel, and W. V. Meyer, Phys. Rev. Lett. {\bf 88}, 015501 (2002). "Colloidal hard-sphere crystallization kinetics in microgravity and normal gravity", ZD Cheng ,JX Zhu ,WB Russel ,WV Meyer ,PM Chaikin,APPLIED OPTICS {\bf 40}, 4146-4151 (2001). "Phase diagram of hard spheres", Cheng Z, Chaikin PM, Russel WB, Meyer WV, Zhu J, Rogers RB, Ottewill RH, MATERIALS \& DESIGN,{\bf 22}, 529-534 (2001). Phonons in an Entropic Crystal Zhengdong Cheng, Jixiang Zhu, William B. Russel, P. M. Chaikin, Phys. Rev. Lett. 85, 1460 (2000) Nature of the divergence in low shear viscosity of colloidal hard-sphere dispersions, Cheng ZD, Zhu JX, Chaikin PM, Phan SE, Russel WB, PHYSICAL REVIEW E65 (4): art. no. 041405 Part 1 APR 2002 Good diblock references: F. S. Bates, and G. H. Fredickson, Physics Today Feb, 1999 F. S. Bates, Science, 251, 898 Some of our stuff is in: C. Harrison, D.H. Adamson, Z. Cheng, J.M. Sebastian, S. Sethuraman, D.A. Huse, R.A. Register, and P.M. Chaikin, "Mechanisms of Ordering in Striped Patterns", Science, 290, 1558-1560 (2000). R. R. Li, P. D. Dapkus, M. E. Thompson, W. G. Jeong C. Harrison, P. M. Chaikin, R. A. Register,D. H. Adamson, Dense Arrays of Ordered GaAs Nanostructures by Selective Area Growth on Substrates Patterned by Block Copolymer Lithography, APPL PHYS LETT 76: (13) 1689-1691 (2000)

  2. Diblock Copolymer Nanolithography Spheres Cylinders Lamellae

  3. Monolayers on a substrate

  4. collaboration with R.R. Li, P.D. Dapkus, and M.E. Thompson (USC)  use MOCVD to selectively grow GaAs dots on substrate, through holes in removable “mask” GaAs GaAs GaAs GaAs GaAs GaAs polymer SiNx (15 nm) ozone MOCVD CF4 RIE wet etch

  5. GaAs Dots Have Narrow Size Distribution TMAFM tip GaAs (001) dot diameter (FESEM) height above SiNx (TMAFM) Number of Dots diameter: 23 ± 3 nm overall height: 14 ± 2 nm tapping-mode atomic force microscopy (TMAFM) Size (nm)

  6.  395 K 466 K Orientational Correlation length Average Distance between Disclinations 2 ~ -1/2  t1/4

  7. DEPTH PROFILING AN ISLAND A B Fred, 0.5 point blur. Figure 2. TOP MIDDLE D C BOTTOM 500 nm

  8. Nature Feb. 6,1965 For Circular area two loops are essential Topological equivalent Three loops and one Triradius Two Loops

  9. Analysis of a micrograph 100 nm /3 0 Disclinations : “5” and “7” Steps : 1. Locate Spheres 2. Triangulate Lattice 3. Locate disclinations 4. Locate dislocations 5. Create orientation field 6. Color-map

  10. Measuring Correlation Length x6 • All sphere centers are located and the inter-sphere triangulation lattice produces the local “bond-orientation” angle. • We define e6iq(x) as our hexatic order parameter to calculate x6, similar to x2. Correlation Function Images 09169878 250 nm x6~130 nm~4.5 d0

  11. Time Dependence of Correlation Length t1/4 shift data by aT, taking 398K as reference (nm) t/aT e:\papers\hexaticcoarsening\master 1

  12. dislocations Color Lookup Table 40nm Step Edge

  13. Mask PS/PI Substrate Substrate Without mask With mask “perfect alignment with Mask and Pressure S. Chou C. Harrison, P. Chaikin, & R. Register

  14. Effect of Diblock Copolymers on the Quantum Hall Effect a T=0.3K unpatterned T=0.3K patterned Vg=0.1 m 1 m 3.0 3.0 30 25 2.5 2.5 20 2.0 2.0 Hall Resistance Rxy (kW) 15 1.5 1.5 Longitudinal Resistance Rxx (kW) Longitudinal Resistance Rxx (kW) 1.0 1.0 10 5 0.5 0.5 0.0 0.0 0 0 0 12 12 2 2 6 6 8 8 4 4 10 10 Magnetic Field B (T) Magnetic Field B (T) Chaikin, Register, Shayegan, Bhatt The periodic modulation induced by the triangular polymer lattice lifts the degeneracy of the Landau levels, creating a commensurability-related sub-band structure (Hofstadter butterfly) which should cause extra peaks to appear in the longitudinal resistance.

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