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麻省理工的计算光子晶体的程序

  * Eliminated output-copies input variable; if you want to visualize
    multiple unit cells, you should use mpb-data.

  * Added new "nothing" material that punches a hole through other
    objects to the background.  (This is distinct from default-material
    when epsilon-input-file is used, or for compute-energy-in-objects.)

  * Fixed inability of MPB 0.13 to run under an old version (1.2) of Guile.

  * Now gives an error if k-point or dielectric tensor is incompatible with
    run-te/run-tm, or if the dielectric tensor is not positive-definite.

  * Default to vendor cc instead of gcc, so that C and Fortran compilers
    are in sync.  (We default to the vendor f77 because it was probably
    used to compile LAPACK/BLAS, and Fortran libraries are picky.)

  * The manual now cites our recent publication on the methods behind MPB.

  * Bug fix in compute-energy-in-object-list for non-orthogonal lattices.

  * Bug fix in combine-band-functions and other functions of band functions,
    which did not handle functions of no arguments ("thunks") correctly
    (crashing with an error message).  Thanks to Michelle Povinelli for
    the bug report.

  * Fixed a floating-point sensitivity bug in mpb-data that could cause
    a crash on the Alpha; thanks to Dominique Caron for the bug report
    and debugging information.

MPB 0.13 (1/7/2001)

  * Can now take advantage of inversion symmetry in the geometry, gaining
    at least a factor of two in speed and a factor of two in memory.
    To use this, you configure MPB with --with-inv-symmetry; the resulting
    executable is installed as "mpbi" and only supports inversion symmetry,
    so you will usually want to install the ordinary MPB as well.

  * Added new eigensolver-block-size input variable, so that MPB can
    optionally solve for only a few bands at a time instead of all
    at once, reducing memory requirements and often increasing speed.

  * Improved handling of the singular (zero-frequency) solutions at
    the Gamma (k=0) point.  This k point should no longer converge
    slowly (or cause additional problems in the targeted eigensolver).

  * Manual updates: please see new referencing suggestions; expanded table
    of contents; we now use more conventional units in diamond/fcc example.

  * You can now pass a "thunk" (function of no arguments) to run, and
    it will be evaluated once per k-point (instead of once per band
    per k-point as for ordinary band functions).

  * compute-field-energy function now also returns the fraction of the
    energy in the various field components.  Thanks to Karl Koch
    for the suggestion.

  * The filename-prefix variable is now read each time an output function
    is called, instead of once per (run), so it can be changed frequently
    if desired.  Thanks to Karl Koch for the suggestion.

  * Added first-brillouin-zone function to transform an arbitrary
    k-point into an equivalent point in the first Brillouin zone.
    Thanks to Payam Rabiei for the suggestion.

  * In mpb-data, the center of the output cell is now always identical
    to the origin of the coordinate system.  Thanks to Michelle
    Povinelli for pointing out this deficiency.	

  * Used improved spherical-quadrature formula in computing the
    effective dielectric tensor in 3d; this should increase accuracy
    somewhat at lower grid resolutions.  Thanks to Doug Allan for
    helpful discussions.

MPB 0.12 (7/9/2000)

  * Added fix-*field-phase functions to allow a deterministic phase
    in the output fields, thanks to a suggestion by Doug Allan.

  * Added group-velocity calculation functions (display-group-velocities,
    etcetera).

  * Added -e x,y,z option to mpb-data so that you can now specify
    an orientation of the output cell (e.g. to make the first axis
    the 111 direction of an fcc crystal).

  * Added (index n) substitute for epsilon property of dielectrics,
    equivalent to (epsilon (* n n)).

  * Documented new libgeom features: cone geometric object, coordinate
    conversion functions (reciprocal->lattice, lattice->cartesian, etc.),
    and vector/matrix rotation.

  * compute-field-energy now returns the total, unnormalized energy
    in the corresponding field; combined with compute-energy-in-objects,
    this makes it easy to do some perturbation theory and related
    calculations.

  * Eigensolver improvements.  Periodic reorthogonalization and
    renormalization to combat some numerical problems. New 
    line-minimization code, included with permission from MINPACK-2
    by Jorge More.

  * Fixed breaking of 90-degree rotational symmetry-breaking by the mesh
    in 2d; thanks to Jim West and Doug Allan of Corning for the bug
    report.  (In general, some symmetry-breaking by the discretization
    seems hard to avoid, however.)

  * Fixed bug in field output routines that could cause crashes
    for grid sizes not a multiple of 4.

  * Bug fix in dielectric function construction for 2d systems: we
    now use the xy plane at z=0 as documented, instead of z=-0.5.

MPB 0.11 (2/12/2000)

  * configure script can now detect and link ATLAS 3.0 accelerated BLAS.

  * Added band-range-data output variable.

  * Running mpb-data multiple times on the same file now replaces
    the results of the previous run, instead of appending -new2,
    -new3, etcetera.

  * Fixed bug in run-even/run-odd that could seriously slow or even
    prevent eigensolver convergence.  Thanks to Payam Rabiei for the
    bug report.

  * Fixed compilation --without-hdf5, or when HDF5 is not found.  Thanks
    to Rajesh Rengarajan for the bug report.

MPB 0.10 (1/28/2000)

  * Added mpb-data utility for post-processing data (e.g. for unskewing
    non-orthogonal lattices).  See the data analysis tutorial or
    man mpb-data for more information.

  * Added new data analysis tutorial to the manual, describing how to
    analyze and visualize the results of two sample calculations.

  * Added support for a new material type, dielectric-anisotropic, so
    that you can specify arbitrary real/symmetric dielectric tensors.

  * Added new output-at-kpoint function to make it easier to output
    fields only at a single k-point in a band-structure calculation.

  * When outputting fields, output all field components (x, y, z, and
    real and imaginary parts) to a single HDF5 file.  Also include info
    on the lattice and k-point vectors to facilitate post-processing.

  * Added new subsection to the installation manual describing some
    generic installation path issues on Unix that were confusing people.

  * Use CPPFLAGS environment variable instead of the less-standard
    INCLUDES to pass -I flags to the configure script (for header files
    in non-standard locations).

  * Added diamond.ctl example file for a 3d diamond (fcc) lattice of spheres.

  * Added (brief) mpb man page.

  * Fixed z-parity output and run-even/odd functions for 2d grids.

  * Fixed bug in output-dpwr-in-objects.  Thanks to Mihai Ibanescu for
    the bug report.

  * Compilation fixes.  We need to set SHELL in the Makefile for make on
    some systems.  Also added rule to insure ctl-io.h is created before
    main.c is compiled.  Thanks to Christoph Becher for the bug reports.

MPB 0.9.1 (1/7/2000)

  * Fixed eigensolver bug where special handling of Gamma (k=0) point could
    screw up convergence for subsequent k-points, causing incorrect results.

  * Fixed behavior of filename-prefix input variable; thanks to Karl Koch
    for the bug report.

MPB 0.9 (1/2/2000)

  * Added run-even and run-odd functions, so you can now compute only
    even/odd states (with respect to a z=0 mirror plane) in systems with
    sufficient symmetry.  See also the new z-parity output variable.

  * Added epsilon-input-file variable, so that you can now read an
    arbitrary dielectric function from a file.

  * Field file names now include the polarization (e.g. ".tm").

  * Some optimizations in the eigensolver.

  * Some documentation improvements; thanks to Edmond Chow for his comments.

  * configure should work even when there is no Fortran compiler on your
    system (assuming your BLAS, etc., libraries work without Fortran libs).
    Thanks to Antti Renko for the bug report.

  * Fixed problems detecting BLAS and LAPACK shared libraries in configure.
    Thanks to Karri Varris for the bug report.

  * Fixed trailing spaces in sed command, which were breaking 'make install'
    on some systems.  Thanks to Ron Chase for the bug report.

MPB 0.8.1 (11/22/1999)

  * Added output-hfield-x, output-dfield-y, etcetera, functions for
    outputting only specific field components (see manual reference section).

  * Sped up HDF5 field output routines.

  * Added output-copies variable to set the number of periods output by
    the band output functions (see manual reference section).

MPB 0.8 (11/19/1999)

  * Initial public release.