Attosecond science is based on steering electrons with the electric field of well controlled femtosecond laser pulses. It has led to the generation of extreme-ultraviolet pulses with a duration of less than 100 attoseconds (ref. 3; 1 as = 10(-18) s), to the measurement of intramolecular dynamics (by diffraction of an electron taken from the molecule under scrutiny) and to ultrafast electron holography. All these effects have been observed with atoms or molecules in the gas phase. Electrons liberated from solids by few-cycle laser pulses are also predicted to show a strong light-phase sensitivity, but only very small effects have been observed. Here we report that the spectra of electrons undergoing photoemission from a nanometre-scale tungsten tip show a dependence on the carrier-envelope phase of the laser, with a current modulation of up to 100 per cent. Depending on the carrier-envelope phase, electrons are emitted either from a single sub-500-attosecond interval of the 6-femtosecond laser pulse, or from two such intervals; the latter case leads to spectral interference. We also show that coherent elastic re-scattering of liberated electrons takes place at the metal surface. Owing to field enhancement at the tip, a simple laser oscillator reaches the peak electric field strengths required for attosecond experiments at 100-megahertz repetition rates, rendering complex amplified laser systems dispensable. Practically, this work represents a simple, extremely sensitive carrier-envelope phase sensor, which could be shrunk in volume to about one cubic centimetre. Our results indicate that the attosecond techniques developed with (and for) atoms and molecules can also be used with solids. In particular, we foresee subfemtosecond, subnanometre probing of collective electron dynamics (such as plasmon polaritons) in solid-state systems ranging in scale from mesoscopic solids to clusters and to single protruding atoms.

Although Bose-Einstein condensates of ultracold atoms have been experimentally realizable for several years, their formation and manipulation still impose considerable technical challenges. An all-optical technique that enables faster production of Bose-Einstein condensates was recently reported. Here we demonstrate that the formation of a condensate can be greatly simplified using a microscopic magnetic trap on a chip. We achieve Bose-Einstein condensation inside the single vapour cell of a magneto-optical trap in as little as 700 ms-more than a factor of ten faster than typical experiments, and a factor of three faster than the all-optical technique. A coherent matter wave is emitted normal to the chip surface when the trapped atoms are released into free fall; alternatively, we couple the condensate into an 'atomic conveyor belt', which is used to transport the condensed cloud non-destructively over a macroscopic distance parallel to the chip surface. The possibility of manipulating laser-like coherent matter waves with such an integrated atom-optical system holds promise for applications in interferometry, holography, microscopy, atom lithography and quantum information processing.

We report a source of free electron pulses based on a field emission tip irradiated by a low-power femtosecond laser. The electron pulses are shorter than 70 fs and originate from a tip with an emission area diameter down to 2 nm. Depending on the operating regime we observe either photofield emission or optical field emission with up to 200 electrons per pulse at a repetition rate of 1 GHz. This pulsed electron emitter, triggered by a femtosecond oscillator, could serve as an efficient source for time-resolved electron interferometry, for time-resolved nanometric imaging and for synchrotrons.

Ultrafast electron dynamics in solids under strong optical fields has recently found particular attention [1][2][3][4][5][6][7][8][9] .In dielectrics and semiconductors, various light-field-driven effects have been explored, such as high-harmonic generation 1-4 , sub-optical-cycle interband population transfer 5,6 and nonperturbative increase of transient polarizability 7 . In contrast, much less is known about field-driven electron dynamics in metals because charge carriers screen an external electric field in ordinary metals 7,8,10 . Here we show that atomically thin monolayer Graphene offers unique opportunities to study light-field-driven processes in a metal. With a comparably modest field strength of up to 0.3 V/Å, we drive combined interband and intraband electron dynamics, leading to a light-fieldwaveform controlled residual conduction current after the laser pulse is gone. We identify the underlying pivotal physical mechanism as electron quantum-path interference taking place on the 1-femtosecond (10 −15 second) timescale. The process can be categorized as Landau-ZenerStückelberg interferometry 11 . These fully coherent electron dynamics in graphene take place on a hitherto unexplored timescale faster than electron-electron scattering (tens of femtoseconds) and electron-phonon scattering (hundreds of femtoseconds) 12-15 . These results broaden the scope of light-field control of electrons in solids to an entirely new and eminently important material class -metals -promising wide ramifications for band structure tomography 3,6 and light-fielddriven electronics 8 .Graphene is an ideal platform to extend the concept of light-field-driven current control to metals. Even though the metallic nature of graphene is reflected in its excellent carrier mobilities 16,17 , the carrier concentration is low compared with conventional metals and thus screening due to free carriers is negligible at optical frequencies 18 . Therefore, strong optical fields can be generated in graphene. In addition, graphene, in particular epitaxial graphene on SiC (0001), is one of the most robust materials available 17,19 , and can thus withstand high laser intensities. Moreover, the optical response of graphene is broadband and ultrafast 17 . Earlier photocurrent studies in graphene revealed that photocarriers are generated on an ultrashort timescale of tens of femtoseconds 12,13 , associated with efficient and fast carrier heating 14,15,20 . Still, the timescale of these experiments is limited by the duration of the laser pulse (envelope) because the photocarrier generation is driven by optical absorption, which is governed by the cycleaveraged light intensity.Here we show that a current induced in graphene by few-cycle laser pulses is sensitive to the electric-field waveform, i.e., the exact shape of the optical carrier field of the pulse, which is controlled by the carrier-envelope phase (Fig. 1a). As will be shown, the main mechanism of this waveform-dependent current generation is based on a large modulation of the interband coup...